The new drug will not be put on the market ____ it has proved safe on humans.

admin2011-06-17  19

问题 The new drug will not be put on the market ____ it has proved safe on humans.

选项 A、if
B、until
C、since
D、when

答案B

解析
转载请注明原文地址:https://kaotiyun.com/show/XZfK777K
0

最新回复(0)