问题

Lately some scientists are experimenting _ white mice to __ this kind of medicine

A:on,try on
B:with, test on
C:on ,test out
D:with,carry out

正确答案是：

同类题型

This problem is said _____ three times

Everyone kept silent and tried to come up with an idea to _________ this problem.

some views in the old edition of Three Character Classic, some schools in Hubei Province demand to delete those sentences.

He spoke at the meeting and said that three years in high school ________ not long[ ]

The message you intend to convey through words maybe the exact opposite of ___________ others actually understand