Through a （） pump, the liquid is transferred from the suction to the discharge by the mechanical variation of the volume of a chamber or chambers.

Before liquid can flow into a pump, the air in the suction line must be （） sufficiently to cause the liquid to flow into the suction chamber.

A centrifugal pump vibrates excessively during operationUpon disassembling the pump it is found that the impeller is out of balanceWithout an available spare, you should （）.

Verbal presentation of new words means that the meaning of a second language word is demonstrated through concrete objects, visual aids, or through mime and acting.（）

To absorb the wear resulting from impeller rotation and abrasives in the liquid, a centrifugal pump is usually fitted with （）.

A declaration made by the Master before a PRC Consul，giving particulars regarding heavy weather or other incidents which may have caused damage to the vessel or cargo，through no fault of the vessel，her officers，or crew is a(n)（）.

The valve which is most suited for regulating the flow through a pipeline is a （）

When installed for bilge pumping or ballast duty, centrifugal pumps require a （） to remove air from the suction pipe.

Which of the following pumps are self-priming, and can deal with liquid from a level below the pump（） (1) ejector (2) screw (3) centrifugal

The cleaned heated oil, after passing through the centrifuges, is to be pumped to a （）.

The （） is used to measure the volume of a liquid or gas through a pipeline within any given period of time.

The discharge flow of a reciprocating pump is （）.