I seem/appear to have seen him somewhere.

　　我好像在哪儿见过他。

　　4.can't help but...不由得......

　　【典型例句】

　　I can't help but wonder what will happen.

　　我禁不住想要知道会发生些什么。

　　I can't help but think that it was a mistake.

　　我不禁认为那是一个错误。

　　I can't help but love her.

　　我不禁爱上了她。

　　He can't choose but do it.

　　他只好做这件事了。

　　【知识归纳】

　　cannot help but;cannot but;cannot choose but之后的不定式一般都不带to,常译为"不得不"。

　　【相关链接】

　　can't/couldn't help doing忍不住

　　I couldn't help laughing when I saw her funny expression.

　　看到她滑稽的表情，我禁不住大笑起来。

　　I couldn't help crying.

　　我禁不住哭了。

　　5.I couldn't agree with you more.否定词与比较级连用表示肯定的意义

　　【典型例句】

　　I've never heard a better voice.

　　我从未听过这么好的嗓音。

　　They couldn't have done better.

　　他们打得好极了。

　　It couldn't be worse.

　　太糟了。

　　【相关链接】

　　You cannot be too careful.你越细心越好。

　　We cannot praise him too much.再怎样称赞他都不过分。

　　You can't be careful enough when driving.

　　开车时再小心也不为过。