牛津譯林英語小學(xué)五年級(jí)知識(shí)點(diǎn)梳理

1、五年級(jí)英語下冊總復(fù)習(xí)教案5B Unit 1 Cinderella、單詞:remember 記住mushroom 蘑菇question 問題hurt受傷prince EErpfairy仙女why為什么because 因?yàn)閏lothes 服裝pick采摘put on 穿上take off 脫下understand 理解let讓late遲的before在以前fit合身have to不得不，必須try on 試穿be bad for有害的party聚會(huì)leave behincdUT,丟下help幫助、詞組：the prince ' s hOUSeT的宮殿sad如此傷心back回來to不得不ev

2、ery house拜訪每一間屋子tales童話故事King美猴王some mushrooms找至U一些蘑菇a dress畫一條連衣裙her friend為她的朋友some snacks吃一些零食a drink 喝一杯well很合適so nice看起來那么漂亮't understan壞能理解like to do想要做某事bad for us對(duì)我們有害off the shoes脫下鞋子to the party 參加舞會(huì)fairies三個(gè)仙女it on試穿它to go不得不走twelve o ' clock 12 點(diǎn)以前the parties在那些聚會(huì)上clothes美麗的衣服lot

3、 of mushrooms 許多蘑菇the tree在樹下on the shoe 試穿鞋子them吃了它the girl找到女孩can ' t you/爾為什么不能behind丟下up趕快some drinks找到一些飲料question words些疑問詞me適合我a picture for me 為我畫一幅畫a drink喝一份飲料so nice看起來那么漂亮at school在校學(xué)習(xí)a story about 讀一個(gè)有關(guān) 的故事42. pick a big and red mushroom 采個(gè)又大又紅的蘑菇三、句子：and help me.過來幫我。are you so sad

4、, dear親愛的，為什么你這樣傷心I don' t have any nice clothes or shoes.因?yàn)槲覜]有任何漂亮的衣服和鞋子。up!快點(diǎn)！can eat them.我們可以吃它們了。a pity!真可惜！can' t you go to the party你為什么不能去參加舞會(huì)foot hurts!我的腳受傷了！like reading stories about the Monkey King and Nezha. 我喜歡讀猴王和哪吒的故事。 these mushrooms are bad for us.因?yàn)檫@些蘑菇對(duì)我們有害的。has a good t

5、ime at the party.灰姑娘在舞會(huì)上度過了美好時(shí)光。girls try on the shoe, but it does not fit.許多女孩試穿這只鞋，但是不合適。is Yang Ling not at school today 楊玲為什么今天不在學(xué)校does Nancy take off her coat南希為什么脫下她的外套leaves a shoe behind. 她留下一只鞋。Unit 2 How do you come to school 知識(shí)點(diǎn)、單詞near在附近by 乘（汽車、火車等）bus公共汽車，大巴 士ship輪船metro地鐵taxi出租車，的士bike

6、自行車plane飛機(jī)train火車ride騎車show給看basket籃子city城市street 街，街道young年幼的on foot 步行二、短語come to school 至U學(xué)校來your new home 你的新家far from 離 遠(yuǎn)by bus乘公共汽車near school在學(xué)校附近on foot步行by metro乘地鐵by taxi乘出租車taxi driver出租車司機(jī)by car乘小轎車by bike騎自行車by plane乘飛機(jī)by ship乘輪船by train乘火車on the street 在街上through the trees 穿過樹林taxi dri

7、ver出租車司機(jī)get there到達(dá)那里in the basket在籃子里think so認(rèn)為如此too young太年輕了，太小了go to school 去學(xué)校show to .向 Mtfwant to+動(dòng)詞原形想要f|a new bike一輛新的自仃車|the wheels on the bus 公共汽車的輪子sit in the basket坐在籃子里go round and round 轉(zhuǎn)啊轉(zhuǎn)、句型you like your new home 你喜歡你的新家嗎解析：do是助動(dòng)詞，其第三人稱單數(shù)形式是 does,否定形式分別為：don' t和doesn'°t

8、 助動(dòng)詞開頭的句子是一般疑問句，一般用“Yes, do/doe喊'"No,don' t/doesn來回答。do you live你住在哪里解析：where是特殊疑問詞，用來引導(dǎo)特殊疑問句，其回答不能簡單地回答 yes或者no, 而是要根據(jù)具體所問來回答，比如這里可以用“I live表示方位的詞語”來回答。當(dāng)主語是第三人稱單數(shù)時(shí)，則用“Where doeslive來提問，回答時(shí)謂語動(dòng)詞也相應(yīng)地使用其第三人稱單 數(shù)形式".lives。”do you come to school你是怎樣到學(xué)校來的解析：這里提問的是交通方式，回答一般用by+交通工具來回答，例如：b

9、y bus, by train等;注意：當(dāng)表示步行這種交通方式時(shí)不用by,用on foot。當(dāng)主語是第三人稱單數(shù)時(shí)，用“Howdoescome to school來提問，回答同樣用第三人稱單數(shù)來回答。wants to show his bike to Sam.鮑比想要把他的自行車給山姆看。解析：want to想要做某事，想要某物是want后面直接加某物，想要做某事"want+to+動(dòng)詞原形”。四、語法1 .詢問某人住在哪里的句型：Where do/does live及其回答：live/lives 一般情況下用"Where dolive和'".live來問&

10、#39;和答。當(dāng)主語是第三人稱單數(shù)時(shí)，用 "Where doeslive和'".lives來問'和答。2 .詢問某人如何到某地的句型"How do/does及其回答".by/on 一般情況下用 "How do和".by/on來問和答。 當(dāng)主語是第三人稱單數(shù)時(shí)，用“How does和".by/on來問和答。五、主要句子：1. Where do you live 你住在哪里 I live near school. 我住在學(xué)校附近。2. How do you come to school你是怎么來上學(xué)的I come

11、 to school by bike .我騎自行車來上學(xué)。3. What about you 你呢4. I live on Moon Street.我住在月亮街。5. I live in Sunshine Town.我住在陽光城。5B Unit3 Asking the way一、詞組：ask the way 問路want to =would like to 想要（做）get to the cinema 至U達(dá)電影院get home 至U家get to your home 到你的家the new clothes and shoes 新衣服和新鞋子get on上車get on the metro

12、上地鐵get of下車at Park Station 在公園站walk to Moon Street步行去月亮街next to it在它旁邊come out from 從出來on Sun Street在太陽街can ' t fin漱不到ask a policeman for help 向一位警察求助excuse me 打擾了go along this street 沿著這條街直走walk along this street 沿著這條街直走turn right 向右轉(zhuǎn)turn left at the second traffic light 在第二個(gè)交通燈處向左轉(zhuǎn)on your righ

13、t在你的右邊on your left在你的左邊see a new film 看一部新電影go to City Cinema去市電影院wait for the bus 等公交車at the bus station 在公交車站go by bus 乘公交車去get in a taxi上了一輛出租車too many cars 太多汽車了so many這么多take the metro 乘坐地鐵be over結(jié)束too late 太晚了from your school 從你的學(xué)校in the shoe shop 在鞋店which to choose 選哪一個(gè)二、句子：Ling wants to visi

14、t Su Hai' s newhome日參觀蘇海的新家。2. How do I get to your home 我怎樣到你家3. How does Yang Ling get to Su Hai楊玲劍ome 海家4. You can take the metro.你可以乘地鐵。5. You can get on the metro at Park Station and get off at City Library Station.你可以在公園站上地鐵，在市圖書館下車。6. Then, walk to Moon Street.然后，步行去月亮街。7. My home is next

15、 to it.我家就在它旁邊。8. Yang Ling comes out from City Library Station.楊玲從市圖書館站出來。9. She asks a policeman for help.她向一位警察求助。10. Excuse me, how do I get to the bookshop on Moon Street打擾一下，我怎樣到達(dá)月亮街上的圖書館11. Turn right at the traffic light.在交通燈處向右轉(zhuǎn)。12. You can see the bookshop on your right.你可以看見書店就在你的右邊。13. S

16、he walks along Moon Street.她沿著月亮街走。14. We can go by bus.我們可以乘公交車去。15. They wait for the bus at the bus station. 他們在公交車站等車。16. The bus is full.公交車滿載了。17. Let ' s gdntoctinema by taxi.讓我們乘出租車去看電影。18. Let ' s take the metro:我們乘地鐵。三、知識(shí)介紹：問路當(dāng)我們來到一個(gè)陌生的地方時(shí)，問路恐怕是避免不了的，問路通常包括四個(gè)方面的內(nèi)容：(a) 引起話題： Excuse

17、me (b)詢問路在何方：Where is (c)指路：Go long (d)表達(dá)謝意：Thank you.常見的表達(dá)方式有：a引起話題：Excuse me, where is b詢問路在何方：Can you tell me the way to Can you show me the way to Can you tell me how to get to Could you tell me how to get toHow can I get to Would you tell me the way toWhich is the way to Would you please show m

18、e the way toWhere's Which is the way to Is there a near here c指路：Go along the stre et. Go down the street. Its on Road./ Its in Street.Turn right / left at the crossing.Take the turning on the right / left.Go along Road, turn right/left at Road.Then go along RTae place is on your right/left.You

19、can take bus No .and get off at the stop.It ' s near / beside / between theIt ' s over there.d表達(dá)謝意：Thank you very much.Thanks a lot.Many thanks.路程問答法：How far is it from hereIt ' s about metres/eiremaway.It ' s about minutes ' walk from here.四、語音：sh / ? / sheep ship shoe shop she

20、shirt short shout shoulder shinyt know whi（Sharon is in the shoe shop. She likes shiny shoes. But there are so many, she doesnto choose!莎倫在鞋店里。她喜歡發(fā)光的鞋子。但是有這么多的鞋子，她不知道選哪一雙了。Unit 4 Seeing the doctor 知識(shí)點(diǎn)總結(jié)四會(huì)單詞feel感覺，感到 should 應(yīng)該 have a rest休息 toothache 牙疼 anything 任何東西 二、語音 ch f / t ?/ chair chicken lu

21、nch much teach/ k / headache toothache二、短語：1. see the doctor看醫(yī)生，看病2. be ill 生病3. go to see the doctor 去看醫(yī)生，去看病4. have a headache （患了）頭疼5. feel cold 感覺冷6. Let me check.讓我檢查一下。7. have a fever（得了）發(fā)燒8. have a rest at home 在家休息9. take some medicine 吃一些藥some warm water 喝一些溫水11. have a toothache （患了）牙疼12.

22、go to see the dentist 去看牙醫(yī)'t eat anything不能吃任何東西14. eat a lot of sweets 吃許多糖果15. should't eat too many sweets 不應(yīng)該吃太多糖果one's teeth刷某人的牙17. in the morning 在早晨/在上午18. before bedtime 上床睡覺前/就寢前an ice cream 吃一個(gè)冰淇淋TV看電視21. sit on a bench坐在一個(gè)長凳上chicken for his lunch 午飯吃雞肉23. like Chinese food ve

23、ry much非常喜歡中國的食物24. go to China in March 在三月去中國temperature 你 的體溫in the hospital在醫(yī)院里幫忙to see him 來看他28. be （very） happy to do（指動(dòng)詞原形）sth.很高興去做某事29. can't hear well不能聽得清楚to the hospital 來醫(yī)院31. point at his long neck指著他的長脖子32. My neck hurts.我的脖受傷了。33. feel tired 感到累34. in the library在圖書館里not eat or

24、drink either 也不應(yīng)該吃喝about illnesses 討論疾病some advice 給些建議38. 牙：tooth（單數(shù)）-teeth（算數(shù)）a rest 休息/休息一"會(huì)a lot of rest=have lots of rest 多休息41. have a good rest 好好休息三、句型（能聽、說、讀、寫、用下列句式）1. What's wrong with you 你怎么了I have a headache. I feel cold.我頭疼。我感覺冷。3. What should I do 我應(yīng)該怎么做You should have a res

25、t at home.你應(yīng)該在家休息。5. You should take some medicine and drink some warm water. 你應(yīng)該吃些藥，喝些溫水。6. He goes to see the dentist.他去看牙醫(yī)。7. I can't eat anything.我不能吃任何東西。8. You should brush your teeth in the morning and before bedtime.你應(yīng)該在早晨和睡前刷牙。11. How do you feel now你現(xiàn)在感覺怎么樣13. Can you help me你能幫助我嗎14.

26、Giraffe points at his long neck.長頸鹿指著他的長脖子。9. Why does he have a toothache 他為什么牙疼is sitting on a bench.查理正坐在一個(gè)長凳上。's going to China in March.他將要在三月去中國。temperature is 102 F.你的體溫是102華氏度。（美國等少數(shù)英語國家用華氏度）temperature is 39 C.你的體溫是 39攝氏度。（我國和其他大多數(shù)國家用攝氏度） 四、語法1 .詢問某人身體狀況的基本句型。（1） What's the matter （

27、with.）= What 's wrong with .（可 +人稱代詞賓格 you, him, her, them, us）I/We/They have 我/我們/他們患了 .He/She/It has他/她/它得了（2） How do you feel now你現(xiàn)在感覺怎么樣I feel.我感覺2. What should + 人稱主格（he/she/we/they ） （Shouldn ' t=should not3. 合成詞：兩個(gè)單詞連在一起合成一個(gè)新詞，前一個(gè)詞修飾或限制后一個(gè)詞。此單元中如： headache> toothache > bedtime4.

28、 too+形容詞/副詞，意思是太.， 如 too many/too high/too hot/too cold5. a also在句中，實(shí)意動(dòng)詞前，特殊動(dòng)詞后，如： She can also swim.也，還too在句尾，肯定句和疑問句都能用，多用于口語。either在句尾，通常用于否定句。6. f something :某事，某物一般用于肯定句。（用在疑問句中表示希望得到肯定回答）I anything:一般用于否定句或疑問句，用來代替something o （用于肯定句可表示任何事物）7. ，吃，如：have a cake、多意詞：have 有，如：have a catcan/can'

29、;t I情態(tài)動(dòng)詞+動(dòng)詞原舉仃/舉辦，如：have a partyshould/shouldn tj得了，患有，如： have a coldfeel ill/cold/hungry/hot8. feel（系動(dòng)詞）+形容詞：表示感覺怎么樣，如,9.主格（主語）Iweyouhesh eitthey賓格（賓語）meusyouhimhe ritthe m形容詞性物主代詞（+名詞）myou ryou rhishe rit stheir小作文:What's wrong with TimTim is ill. He has a fever. He feels cold. He should go to

30、 see the should take some medicine and drink some warm should have a lot of rest at home. He shouldn 't watch TV.注意：本單元出現(xiàn)的（動(dòng)詞+ing）形式，多是動(dòng)名詞，如： seeing,eating,但在Sound time部分：Charlie is sitting on a bench .此句中是現(xiàn)在分詞，在：He's going to China in March. 中，be going to 結(jié)構(gòu)表示主觀意愿的將要做某事5B Unit 5 知識(shí)點(diǎn)詞組：1. he

31、lp our parents幫助我們的父母morning星期六上午him幫助他4. clean the car 洗車breakfast做早飯the kitchen 在廚房the living room 在客廳the floor 掃地his bedroom在他的臥室里10. in the afternoon 在下午11. my cousin我的表弟/表妹12. be busy忙碌的dinner做晚飯14. help her 幫助她the dishes 洗碗16. clean the table 擦桌子17. eat fruit 吃水果newspaper看報(bào)紙19. make the bed 整理

32、床鋪20. wash clothes 洗衣服the study在書房22. listen to her 聽她講grapes種葡萄24. in his garden在他的花園里25. big and sweet 又大又甜pests許多害蟲the grapes在葡萄上28. on Sunday afternoon 在星期天下午29. so sweet 如此甜30. go away 走了，離開31. some ladybirds 一些瓢蟲32. do housework 做家務(wù)me cook dinner 幫我做晚飯34. to be continued 待續(xù)句子：1. It ' s Sat

33、urday morning在是星期六上午。2. My father is cleaning the car.我的爸爸正在清洗小汽車。3. I ' m helping him我在幫助他。4. What are you doing 你在干什么 I ' m cleaning the tab底在擦桌子。5. He grows grapes in his garden.他在他的花園種植葡萄。6. Helen is in the living room.海倫在客廳。7. What is she doing 她在干什么 She is sweeping the floor.她在掃地。8. Wh

34、at is he doing now 他正在干什么 He is sleeping.他正在睡覺。9. -What are they doing now-他們現(xiàn)在在于什么-They are helping their parents.-他們在幫助他們的父母。10. My mother is busy.我的媽媽正忙著。11. She is cooking dinner.她在做晚飯。12. What is Helen doing 海倫在干什么Helen is washing the dishes.海倫在洗碗。13. My grapes are big and sweet.我的葡萄又大又甜。are so

35、me pests on the grapes.葡萄上有一些害蟲。14. The pests go away, but the ladybirds do not.害蟲走了,但瓢蟲們留下了。15. They are eating fruit in the living room.他們在客廳吃水果。16. In the morning, I like to sing and watch the flowers growing. 在早晨，我喜歡歌唱，看花兒生長。17. In the evening, I like to sit and listen to the wind blowing .在晚上，我

36、喜歡靜聽風(fēng)兒吹。18. My mother is cooking breakfast in the kitchen.我的媽媽在廚房里做早飯。作文：A busy dayWe have a busy day. My father is cleaning the car. My mother is cooking. I am making the bed.We are busy but happy.現(xiàn)在分詞：do-doing help-helping sweep-sweeping make-makingclean-cleaningsing-singingcook-cookingeat-eatingw

37、ash-washinggrow-growingwatch-watchingblow-blowingtake-taking5B Unit 6 In the kitchen、詞組:2. come home from a football game 足球賽后回至U家4. meat smells nice 肉聞起來很美味6. wash some vegetables 洗一些蔬菜1. six o ' clock in the eveinng 六點(diǎn)鐘3. cook dinner in the kitchen 在廚房里做飯5. cook meat 煮肉meat with potatoes 燒些土豆燒

38、肉10. in the fridge 在冰箱里7. cook some tomato soup 做番茄湯9. look for some juice 尋找一些果汁11. some orange/apple juice 一些橙汁 /蘋果汁13. eat the meat 吃肉15. you win 你贏了17. come through our little town通過我們的小鎮(zhèn)19. eat with chopsticks 用筷子吃飯21. eat with a knife and fork 用刀叉吃飯23. in Bobby ' s garden 比的花園里25. see two

39、ladybirds on Sam ' s hand看到薩姆手上有兩只瓢蟲27. have seven spots 有七個(gè)斑點(diǎn)29. drive the bad ladybirds and the pests away把瓢蟲和害蟲趕走二、句型：1. That smells nice.那個(gè)聞起來好香。2. Are you cooking meat No,I' mot肉嗎沒有,3. I can ' t wait, DOdtl,我等不及了 ！4. Dinner is ready.晚飯好了。12. Dinner is ready.晚餐準(zhǔn)備好了。14. eat fruit 吃水果1

40、6. the queen 女王，王后18. wear her golden crown 戴著她金色的皇冠20. It ' s yummy!=It ' s deJcous!22. a lot of pests and ladybirds 許多害蟲和瓢蟲24. come to help Bobby 來幫助波比26. catch a ladybird from the grapes從葡萄上抓到一只瓢蟲28. how many spots 有多少個(gè)斑點(diǎn)30. help in the kitchen 在廚房幫忙我沒在煮肉。5. How ' s the meat,Taota的濤，肉

41、的味道怎么樣It ' s yummy,Dld爸，肉好吃。6. You ' re a great co ok 你做菜很棒！7. They have seven sports. 它們有七個(gè)斑點(diǎn)。8. There is some bread in the fridge. 冰箱里有些面包。9. There are three potatoes in the fridge. 冰箱里有三個(gè)土豆。10. Is he looking for some tomatoes Yes, he is.他在找番茄嗎是的，他在尋找。四、語音： 字母組合，qu'在單詞中的讀音/kw/ 如：quick

42、, quiet ,question,quite, queen五、語法總結(jié)：本單元的重點(diǎn)是現(xiàn)在進(jìn)行時(shí)的一般疑問句及其回答，同時(shí)用there be句型呈現(xiàn)了可數(shù)名詞和不可數(shù)名詞的用法?，F(xiàn)在進(jìn)行時(shí)的 一般疑問句結(jié)構(gòu)：Be動(dòng)詞+主語+動(dòng)詞ing+其他t.肯定回答：Yes,主語+be動(dòng)詞。否定回答：No,主語+be動(dòng)詞+not。例:Is he running Yes,he is. /No,he isnArd thtey climbing Yes, they are. /No, they arenThere be句型表示的是某處有(存在)某人或某物"，There be結(jié)構(gòu)強(qiáng)調(diào)的是 存在關(guān)系”。其

43、結(jié)卞勾為There be(is , are)+名詞+ 地點(diǎn)。There be句型中的be應(yīng)和其后出現(xiàn)的主語在數(shù)上一致，即 就近原則”，例如：'There be后接的如果是可數(shù)名詞單數(shù)或不可數(shù)名詞時(shí)，be只能是單數(shù)形式is;4如： There is a book on the desk.i There be后接的如果是 可數(shù)名詞復(fù)數(shù) 時(shí)，一定要用復(fù)數(shù)形式are .如： There are some books on the desk.三，語法There be與have/has用法區(qū)別1、There be句型表示：在某地有某物(或人)2、在there be句型中，主語是單數(shù)， be動(dòng)詞用i

44、s ;主語是復(fù)數(shù)，be動(dòng)詞用are ;如有幾件物品，be動(dòng)詞根據(jù) 最靠近be動(dòng)詞的那個(gè)名詞決定。3、there be句型的否定句在 be動(dòng)詞后加not , 一般疑問句把 be動(dòng)詞調(diào)到句首。4、there be句型與have(has)的區(qū)別：there be表示在某地有某物(或人)； have(has)表示某人擁有某物。5、some和any在there be句型中的運(yùn)用：some用于肯定句，any用于否定句或疑問句。6、and和or在there be句型中的運(yùn)用：and用于肯定句，or用于否定句或疑問句。7、針對(duì)數(shù)量提問的特殊疑問句的基本結(jié)構(gòu)是：How many + 名詞復(fù)數(shù) + are the

45、re + 介詞短語？How much +不可數(shù)名詞 + is there +介詞短語？8、針對(duì)主語提問的特殊疑問句的基本結(jié)構(gòu)是：What' s +H司短語5B Unit7 Chinese festivals【重要詞匯】festival 節(jié)日spring春天January 一月February 二月call 稱呼，叫作together 一起dumpling 餃子May 五月June 六月dragon 龍race 比賽place 地方September 九月October 十月November 十一月climb 爬，攀mountain 山or 或者songbird 鳴鳥knock 敲Hal

46、loween 萬圣節(jié)know 知道【短語歸納】get together with their families 和家人團(tuán)聚eat rice dumplings 吃粽子dragon boat races 龍舟比賽in some places 在一些地方at Mid-Autumn Festival 在中秋節(jié)in September or October 在九月或十月look at the moon at night 晚上賞月eat moon cakes 吃月餅climb mountains 爬山sit in the tree 坐在樹上sing songs to me 唱歌給我聽on the thi

47、rty-first of October 在十月三十一號(hào)dress up 裝扮knock on people ' s dOOrS 們的1on Mother ' s Day母親節(jié)a day for mothers 母親們的一天on the second Sunday of May 在五月的第二個(gè)星期日give their mothers presents 給他們的母親禮物That ' s a good ideO!?主意！talk about the present for Mum 討論給媽媽的禮物 What about a card and some flowers 一張

48、卡片和一些花怎么樣【重難點(diǎn)梳理】1. 傳統(tǒng)節(jié)日 “ ”匯總Spring Festival 春節(jié)Dragon Boat Festival 端午節(jié)Mid-Autumn Festival 中秋節(jié)Double Ninth Festival 重陽節(jié)注意：上面的幾個(gè)傳統(tǒng)節(jié)日，前面的介詞用at拓展：節(jié)日前面的介詞常用兩個(gè)：at和on,具體的區(qū)別如下：不帶day的節(jié)日，用 atat Christmas在圣誕節(jié)帶day的節(jié)日，用 onon Children ' s DOy L童節(jié)on Teachers ' Day 教師節(jié)介詞填空： Spring FestivalChristmas Day2.十二

49、月”大集合January 一月February 二月March三月April四月October 十月May五月June六月July七月August八月September 九月November 十一月December 十二月月份前面用介詞inChristmas is in December.注意：如果表示具體的某一天（幾月幾日），則用介詞onChristmas is on December,25.常見短語summer holiday 暑假寒假：季節(jié)前面也用介詞inIn winter, we can make snowmen.我們可以在冬天堆雪人。我們可以在夏天去游泳。我們可以在春天放風(fēng)箏。5B Unit8 Birthdays一"、詞匯A.單詞Birthday 生日eleventh 第十一together 一起eighth 第八April 四月go shopping 去購物March 三月July 七月August 八月Dec