问题
选择题
They usually have the medicine ______ before putting into the market all over the country. [ ]
A. testing out
B. to be tested out
C. being tested out
D. tested out
答案
答案：D
搜题请搜索小程序“爱下问搜题”
They usually have the medicine ______ before putting into the market all over the country. [ ]
A. testing out
B. to be tested out
C. being tested out
D. tested out
答案：D