動詞do在句中的作用可以概述為四句十二字:"做"實義,助動詞,替前文,強語氣。
作用一:實義do
do作實義動詞時,有do, does, did, done, doing五種形式,還有及物、不及物之分。如:
1. vt. "做;研究;整理;完成"。如:
①The old man does an hour of sport every day.
②She did her homework at home last night.
③Mother was doing the cooking when I reached home.
④Have you done the exercises yet?
2. vi. "行動;工作;進展;足夠"。如:
① Kate does very well in her Chinese.
② How do you do? ③ Well done! ④ That will do.
作用二:助動do
do作助動詞時,只有do, does, did三種形式,無詞義,限用于含行為動詞的一般現(xiàn)在時和一般過去時兩種時態(tài)的否定句和疑問句中。如:
①They don't have any tickets for tonight's concert.
②Kate stayed at home last night, didn't she?
③How many books does the library have?
④She doesn't do the washing in the evening.
作用三:替代do
為避免動詞的重復,使語言簡練,常以do, does, did替代前文所用的行為動詞。如:
①Tom runs much faster than you do.
②-Lucy, can you get some more tea, please? -Sure. I'll do it right away.
②-Who broke the cup?-Mimi did.
③-I like bananas.-So does he.
作用四:語氣do
為突出感情色彩,do常用于祈使句、強調句和倒裝句中,以加強語氣。如:
① Do be careful.
② Don't tell a lie.
③ He did come.
④ -You often go to the park.-So we do.