有一读者问： 我在一篇文章中，遇到下面的对话：
(1)—Take me to 14 Stephens Street, will you?
— Yes. Let me help you in.
这里的 in 如何解释？
“Let me help you in.” 在此的意思是“让我扶你上车吧”。 in 是一小品词，更正确地说，是一介副词 （介词用作副词）。这种介副词除 in 外，还有 out, on, off 等等。它们常用在“及物动词+宾语+介副词”这一结构之中。这是一种非常简便有用的结构。再如：
(2)I'll carry the dog in . （in 在此是介副词）
(3)I bent over the dog and was about to unfasten the leash from the collar when he said, “No, leave that on .” （on在此是介副词）
(4)I helped him out , ... （out 在此是介副词）
另如下面句子中的斜体词皆为用于上述结构的介副词：
(5)We saw some friends off .
(6)I found that she had left her umbrella behind .
(7)The waves turned our boat over .
(8)I want you inside .
(9)Now, push this table under , while I support his arm.
