understand后面接什么

1、In my experience， very few people really understand the problem.据我的经验看，真正理解这个问题的人很少。

2、I quite understand that you need some time alone.我很理解你需要独自静一会。

3、People are often afraid of things they don't understand.人往往对自己不懂的东西感到恐惧。