often后加什么詞性的詞

　　It is not often that you get such an opportunity.

　　你得到這樣的機會，可不是常有的事。

　　Men often don't like to share their problems.

　　男人往往不喜歡把自己的問題告訴他人。

　　We don't often have time to talk.

　　我們常常沒有時間談話。

　　People are often afraid of things they don't understand.

　　人往往對自己不懂的東西感到恐懼。

　　I often think about my friends back home.

　　我常常想起老家的朋友。