A.filtering
B.centrifuging
C.depositing
D.operating
第1题:
A) regulations
B) rules
C) disciplines
D) principles
第2题:
Advise you________engines.
A.stop
B.to stop
C.stopping
D.stopped
第3题:
Category 2 fuel _____________________
第4题:
What is the meaning of the word “gadgets” (Paragraph 4)?
[A] devices [B] tools [C] appliances [D] engines
第5题: