你都不能信任她照顾你的狗，更不用说你的孩子了。

You couldn't trust her to look after your dog, ___let ___alone your child.

我们被令人惊叹的技术所包围，这些技术我们甚至不完全理解，更不用说充分利用了。

We are surrounded by amazing pieces of technology which we do not fully understand, ___let ___alone use to their full capacity.

他连租金都不够，更不用说度假了。

He doesn't have enough money for rent, ___let ___alone a vacation.