Don’t be joking. It’s time to your business.A. take up　B. set out　C. go onD. get down to

问题补充：

Don’t be joking. It’s time to your business.

A. take up

B. set out

C. go on

D. get down to

答案：

A. take up

B. set out

C. go on

(答案→)D. get down to

解析：考查动词短语辨析。A占据，从事于，；B出发，动身；C继续；D开始做；句意：不要开玩笑了。现在是你开始做你自己事情的时候了。根据句意说明D正确。