问题
选择题
___ the safety of gas, the government has checked the city's gas supply system thoroughly. [ ]
A. Having ensured
B. Ensuring
C. To ensure
D. Ensured
答案
答案：C
搜题请搜索小程序“爱下问搜题”
___ the safety of gas, the government has checked the city's gas supply system thoroughly. [ ]
A. Having ensured
B. Ensuring
C. To ensure
D. Ensured
答案：C