冒险的英语短语怎么写

例句：

投资航空公司是非常冒险的生意。

Investing in airlines is a very risky business.

这不是冒险的`时候，他知道他应该按规则行事。

This was not the time to take risks; he knew he should play it by the rule book.

这是一项冒险的举动，但也许能换得更多的时间。

It was a risky operation, but might buy more time.