A: Mike promised to help us.

迈克答应帮助我们。

B: Mike? How can you trust him to help us?

迈克?你怎么能相信他会来帮助我们?

A: Why not?

为什么不能呢?

B: He is too unpredictable. He says anything that pops into his head. And then he forgets it all.

他太让人难以琢磨。他总是想起什么就说什么，可是过后一会儿就忘了一切。