Scrapers are used to （）the rust on the plates.
第1题：
A. remove
B. move
C. get
D. leave
第2题：
29． The writer thinks that people in large cities should __________ ．
A． stop the used water from getting into underground
B． only use the water from the rivers
C． make their used water clean again
D． use as much sea water as possible
第3题：
A、Gas
B、Organic compound
C、Molten salt
D、Water
第4题：
The ______is used to burn oil sludge.
A.clarifier
B.oily water separator
C.incinerator
D.distiller
第5题：
A.is
B.them
C.its
D.they
第6题：
As mentioned,‘grey water’ can be used to＿，
A．wash the car
B．water the garden
C．clean the toilet
D．dispose of wastes
第7题：
What is head tank in the closed cooling water system used for?
A.for the release of air from the cooling water
B.providing expansion room for heated cooling water
C.a place for implementing water and water treatment agent
D.all of the above
第8题：
A、mobile
B、drift
C、shift
D、rotate
第9题：
As mentioned，“grey water”can be used to______.
A．wash the car
B．water the garden
C．clean the toilet
D．dispose of wastes
第10题：
A check line is ______．
A.A safety line attached to a man working over the side
B.Used to measure water depth
C.Used to slow the headway of a barge
D.Used to measure the overhead height of a bridge