单项选择题
A.present B.prevent C.avoid D.provide
It is very necessary that each cylinder （） before the c...
单项选择题It is very necessary that each cylinder （） before the charged air is compressed.
A.is scavenged B.has been scavenged C.be scavenged D.was scavenged
A.is scavenged B.is atomized with fuel oil C.be scavenged D.be atomized with fuel oil
It is very important that each cylinder should be （） sc...
单项选择题It is very important that each cylinder should be （） scavenged before the charged air is compressed.
A.well B.good C.excellent D.respectively
