borrow延续性动词怎么改

borrow延续性动词：keep

How long can I keep this book?

我能借这本书多久

Her grandchildren keep her young.

她的孙子孙女让她保持年轻。

I work out regularly to keep fit.

我经常做运动以保持健康。

My family helps to keep me centred.

家人帮助我保持冷静。

I kept telling myself to keep calm.

我不断叮嘱自己要保持冷静。

I'm very sorry to keep you waiting.

对不起，让你久等了。