She always seems to be sad. 她常常顯得很憂傷。

My advice proved to be wrong. 我的意見證明是錯的。

She appears to have many friends. 他好像有很多朋友。

The weather turned out to be fine. 天氣結果很好。

Circumstances continue to be favorable. 情況仍然是有利的。

He has grown to like studying English. 他漸漸喜歡學英語了。

【注】若所接不定式為to be，通常可以省略。不過，若其后接的是表語形容詞，則to be通常不宜省略。另外，連系動詞look后能否接to be似乎尚有爭論，不過，在現代英語中接to be的現象已較普遍。

(3) sound, smell, feel, taste, become等連系動詞后通常不能接不定式：

誤：These oranges taste to be good. (應去掉to be)

誤：The roses smell to be nice. (應去掉to be)

(4) 有的連系動詞后接的從句可用不定式來改寫：

It seems that she's right. / She seems to be right. 她似乎是對的。

It appears that you have made a mistake. / You appear to have made a mistake. 似乎你弄錯了。