He'd have to be able to see and hear them 24 hours a day.就需要一天二十四小时监视他们

able to能做 ...

It is good to be able to cast aside winter clothes.

能把冬衣搁在一边了，真好。

As I had plenty of money I was able to help her.

我钱很宽裕，能帮助她。

could we set up our home as an observation space能否把自己的家作为观测站

set up建立；树立；创立；安排

It is now our aim to set up a factory.

我们现在的目的是创办一座工厂。

He set up in business as an insurance broker.

他开始从事保险经纪人的职业。

scientist Deb Roy realised that to discover how a child learns to speak...戴布·罗伊意识到要研究孩子习得讲话的过程

learn to学习

I must learn to snatch at every chance to meet him.

我必须学会抓住一切机会同他见面。

A mountaineer must learn to stand the gaff.

一个登山运动员必须学会吃苦。