the only修飾名詞時，它后面習慣上可以加上動詞不定式短語to do，動詞不定式短語一般是用作后置定語的。例句：Mr. William is the only foreign friend to be present at the meeting.

the only相關例句

The only trouble is we won't be here then.

唯一的麻煩是到那時我們就不在這兒了。

The only stipulation is that the topic you choose must be related to your studies.

唯一的要求是你選的題目必須與你的研究科目有關。

The only people there were ourselves.

那里僅有的人就是我們自己。

We were the only people there.

我們是唯一在場的人。

That's the only reason I'm actually going.

這是我確實要走的唯一理由。