如果长期停车，则必须在停火后关掉所有泵，关闭（）、（）、（）阀门。
参考答案：水阀门；氯气；氢气
This room is ___________ that room.
A．as three times big as
B．three times as bigger as
C．three times as big as
D．as big as three times
Mr. Fox fell ill, thus __________ it necessary for us to find another person for his job.
A．having made
B．made
C．making
D．to make
