_______the safety of gas, the government
题型:选择题
问题:
_______the safety of gas, the government has checked the city's gas supply system thoroughly. [ ]
A. To ensure
B. Ensuring
C. Having ensured.
D. To have ensured
_______the safety of gas, the government has checked the city's gas supply system thoroughly. [ ]
A. To ensure
B. Ensuring
C. Having ensured.
D. To have ensured