is necessary
being necessary
to be necessary
it is necessary
第1题:
第2题:
While discharging a tanker,list can be controlled by ______.
A.Shoreside personnel
B.Using a center tank near the bow,discharging as necessary
C.Using wing tanks near the longitudinal center,discharging as necessary
D.Using the after peak tank,loading as necessary
第3题:
A、This being his first visit
B、Never having visited
C、This being his first time to visit
D、Having never been before
第4题:
第5题:
第6题:
A.taste
B.tasty
C.tasteless
D.tasteful
第7题:
第8题:
A.they are needed
B.were necessary
C.it was needed
D.necessary were they to him
第9题:
第10题: