He must be crazy to continue working in the circus after all the close calls he's had.

他这么多次都差点出事还继续在马戏团工作，一定是疯了。

youdao

To be competent in his field, he must develop a working knowledge of this aspect.

为了使自己能胜任所从事工作，必须加深这方面知识。

youdao

To be competent in his field, he must develop a working knowledge of this aspect.

为了使自己能胜任所从事工作，必须加深这方面知识。

youdao