【正文】 它們的構成方法是：先將相應的十位整數(shù)的基數(shù)詞詞尾－ty中的y改成i，然后在加上后綴－eth。要注意其中fifth、eighth、ninth、twelth四個詞的拼法。 第二類： fourth (4th) 第四 fifth (5th) 第五 sixth (6th) 第六 seventh (7th) 第七 eighth (8th) 第八 ninth (9th) 第九 tenth (10th) 第十 eleventh (11th) 第十一 twelfth (12th) 第十二 thirteenth (13th) 第十三 fourteenth (14th) 第十四 fifteenth (15th) 第十五 sixteenth (16th) 第十六 seventeenth (17th) 第十七 eighteenth (18th) 第十八 nineteenth (19th) 第十九 這一類序數(shù)詞共有十六個。first (1st) 第一 second (2nd) 第二 third (3rd) 第三 （在括號里的是縮寫形式，均在阿拉伯數(shù)字后面加上相應序數(shù)詞的最后兩個字母構成，以下各類與此相同。整十先把詞尾y改為ie再加th。twelve→twelfth，五、十二把ve換成f再加th；twenty→twentieth，八去t，九去e后再加th；three→third這三個詞變化特殊，要單獨記；eight→eighth， 解析口訣：one→first，ve要用f替，整十基數(shù)變序數(shù)，先把ty變成tie；要是遇到兩位數(shù)，十位基數(shù)個位序，th最后加上去。juice now. （ ） C. am working’t e in! She B. is working. （ ）A. work C. is flying’t bother me ! I B. flying. （ ）A. is fly C. run B. is runingin the garden. （ ）A. is running. C. is jump parents B. is jumpingon the bed. （ ） A. are jumping C. am siting B. am sittingon the chair now. （ ） A. is sitting二、選擇。 (sing!(fly)in the garden now.5. Look! The bird (sit) on the beach now.3. Don’t e in! I 一、填空1. She 二、用現(xiàn)在進行時完成下列句子:1. ______you__________(fly) a kite? Yes,_______.2. ______you___________(sit) in the boat?3. ______he_____________(talk) with me?4. We_______________(play) football now.5. What_________you__________(do)?6. I_____________(sing) an English song.7. What________he____________(mend)?8. He______________(mend) a car.9. These boys _________ (play) tennis on the playground.10. My mother______________ (cook) in the kitchen.三、選擇1. Look. Lucy is_____ a new bike today.　A. jumping 　B. running 　C. riding 　D takeing2. The children _____ football.　A. is playing 　B. are playing 　C. play the 　D. play a3. They ______TV in the evening. They do their homework.　A. are watching　 B. can’t watching　 C. don’t watch 　D. don’t watching4. Listen! She____ in the classroom.　A. is singing　B. sing 　C .to sing 　D. is sing5. ______are you eating? I’m eating ______ meat.　A. What,some　 B. Which,any　 C. Where,not　 D. What,a6. Is she ____ something? A. eat　 B. eating　 C. eatting　 D. eats7. I can’t catch up with the fashion,because the clothes style_______ all the time.　A. has changed 　B. is changed　 C. is changing 　D. changed! The children_______ basketball on the playground.　A. plays 　B. played 　C. is playing 　D. are playing and Ketty_______ in the lake. Let’s join them,shall we?　A. swim　 B. have swum　 C. swam　D. are swimming’s six in the afternoon. The Greens_______ lunch together.　A. has　 B. are having 　C. have had　D. had had答案：一、1. Are ,flying,I am 　2. Are sitting,　,talking　 4. are plying 　5. are,doing　 singing 　7. is,mending 　8. is mending 　 plying　 cooking　二、　 　 　 　 　　 　 tie sit run dance play （3）以重讀閉音節(jié)結尾的動詞，如結尾只有一個輔音字母，應先雙寫出這一字母，再加—ing。例如：work—working, study—studying.（2）以不發(fā)音的字母e結尾的動詞，先去掉e，再加—ing。 We areWe’re He isHe’s 1)現(xiàn)在進行時的肯定形式：主語+be(am/ is/are)+doing+其他成分　　I am singing . They are writing .　2)現(xiàn)在進行時的否定形式:主語+be(am/ is/are)+not +doing+其他成分　　I am not singing . They aren’t writing .　3）一般疑問句及回答：be(am/ is/are)+ 主語+doing+其他成分　　Am I singing ? Yes ,you are . / No ,you aren’t .　　Are they writing ? Yes ,they are . / No ,they aren’t .　4)特殊疑問句及回答:特殊疑問詞+be(am/ is/are)+主語+doing+其他成分What are you doing ? We are playing (要求就提問內(nèi)容具體回答).縮寫形式如下:　　I amI’m Tom is ing here next 。 go, leave, start, arrive等動詞常與將來時間的狀語連用表示這種意義。Come, 這些天我們正在農(nóng)場摘蘋果。 這學期他們在努力學習嗎？例如： 你們在干什么？我們在打籃球。例如： teaches