現(xiàn)在進(jìn)行時的基本用法
a. 表示現(xiàn)在( 指說話人說話時) 正在發(fā)生的事情。
We are waiting for you.
b. 習(xí)慣進(jìn)行：表示長期的或重復(fù)性的動作，說話時動作未必正在進(jìn)行。
Mr. Green is writing another novel.
(說話時并未在寫，只處于寫作的狀態(tài)。)
She is learning piano under Mr. Smith.
c. 表示漸變的動詞有：get, grow, become, turn, run, go, begin等。
The leaves are turning red.
It's getting warmer and warmer.
d. 與always, constantly, forever 等詞連用，表示反復(fù)發(fā)生的動作或持續(xù)存在的狀態(tài)，往往帶有說話人的主觀色彩。
You are always changing your mind.
典型例題
My dictionary ___, I have looked for it everywhere but still___ it.
A. has lost, don't find B. is missing, don't find C. has lost, haven't found D. is missing, haven't found.
答案D. 前句是一個仍在持續(xù)的狀態(tài)，應(yīng)用進(jìn)行時，由于沒有找到，其影響仍然存在，應(yīng)用完成時，瞬間動詞用于否定式時可用于完成時。
