有一些介词可兼作副词,这种介词亦可称作小品词(particle)。试比较:
My mother is in the house.
我母亲在屋里。(介词)
Is there anybody in?
里面有人吗?(副词)
The programme was broadcast over the radio.
这个节目是通过电台广(介词)
The programme is over.
这个节目播完了。(副词)
请注意下面两句中的与介词形式相同的副词:
He turned over the page.
他翻过书页。(over在此是副词,与turned组成短语动词)
I've put on weight.
我体重增加了。(on在此是副词,与put组成短语动词)
请注意下面两句中的与副词形式相同的介词:
The boat moved slowly down the river.
那船沿河缓缓而下。(down在此是介词)
He climbed up the tree.
他爬上了树。(up在此是介词)
还有少数介词可以兼作连词,如after,before,since,till(until)等。如:
The ball goes up very high after it hits the ground.
这球着地后蹦得很高。
It will not be long before they come back.
他们不久就回来。
I can't make you out. You're so changed since last we met.
我认不得你了。自上次见面后,你可变多了。
Will you be all right until I get back?
在我回来之前你会一切都好吗?