動(dòng)詞不定式 to do 是非謂語(yǔ)動(dòng)詞的一種形式,它除了不能做句子的謂語(yǔ)外,其它任何成分都能做.用于很多固定的詞組如 want to do, want sb. to do , tell sb. to do , decide to do , plan to do ,ask to do ,can't wait to do
It takes sb. +時(shí)間+ to do , 以及 疑問(wèn)詞+ to do ( what to do , how to do it )等等.
過(guò)去式 用于一般現(xiàn)在時(shí)的句子,表示過(guò)去時(shí)的時(shí)間狀語(yǔ)有...ago, last year, just now , yesterday , in 1996 等.
過(guò)去分詞 用于 現(xiàn)在完成時(shí),其構(gòu)成為：主語(yǔ)+have / has +動(dòng)詞的過(guò)去分詞+其它.現(xiàn)在完成時(shí)的時(shí)間狀語(yǔ)有so far , in the last / past few years, over the years ,already, yet , never , just , up to / till now等.
另外,過(guò)去分詞還用于構(gòu)成 被動(dòng)語(yǔ)態(tài) 如:一般現(xiàn)在時(shí)被動(dòng)語(yǔ)態(tài)為: be（am /is /are )+及物動(dòng)詞過(guò)去分詞
一般將來(lái)時(shí)被動(dòng)語(yǔ)態(tài): shall / will +be +過(guò)去分詞