单项选择题
A.is scavenged B.has been scavenged C.be scavenged D.was scavenged
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.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
It is necessary to remove （） from the cooling water spa...
单项选择题It is necessary to remove （） from the cooling water spaces to improve heat transfer.
A.lime B.frost C.scale D.scar
