误：I will come back after a few minutes.

正：I will come back in a few minutes.

析：用作介词, 与一段时间连用表示“在...之后”时, after 与 in 有区别：after 表示以过去时间为起点的一段时间以后, 且通 常与过去时态连用；而 in 则表示以现在为起点的一段时间以 后：He came back after a few minutes.(他几分种后就回来 了)。

◆史密斯先生五点后回来。

误：Mr Smith will come back in five o’clock.

正：Mr Smith will come back after five o’clock.

析：与一点时间连用, 表示“在...之后”，不管是用于过去时态还是将来时态, 均用 after, 不能用 in。如：He will come back after next month.(他将在下个月以后回来)。

◆读罢此信, 他哭了。

误：After reading the letter, tears ran down his cheeks.

正：After he read the letter, tears ran down his cheeks.

正：After reading the letter, he burst into tears.

析：after 引导动名词作状语时，要注意其逻辑主语与句子主语保 持一致。

◆我到达那儿后就给你写信。

误：I’ll write to you after I will get there.

正：I’ll write to you after I get there.

析：after 用作连词引导时间状语从句时，要用一般现在时态表示 将来意义, 而不能直接使用将来时态。

◆警察在追小偷。

误：The policeman was running behind the thief.

正：The policeman was running after the thief.

析：比较：run after 意为“追赶”；run behind 意为“在...后 面跑”。