The _____ of this country comes from its oil.

One very（ ）serious problem is energy. We get a great （ ） of energy we need from

[单选题]B．itterness comes from __________.A． our health problems like heart diseaseB． the anger that lives deep inside our mindC． the person who says something that hurts usD． our relationships with friends and family members

[主观题]The salmon comes back to its birthplace in order to ____________.

[单选题]Itseemsoil________fromthispipeforsometime.We’llhavetotakethemachineaparttoputitright.A．)hadleakedB)isleakingC)leakedD)hasbeenleaking

[单选题]The selection of an oil from the （） depends to a great extent on the operating conditions, the design of the engine and the type of fuel to be burned.A . commercially availableB . commerciallyC . commercial availableD . commerce available

[单选题]"If winter comes, can spring be far behind?" the quoted line comes from ___

The cetane number of a diesel fuel oil indicates its ______.A. ignition qualityB

_______can cause oil flow from water outlet of the oil purifier.A. Oil inlet val

[单选题]The removal of （） from lubricating oil will reduce engine wear and possible breakdowns.A . contaminating waterB . contaminated additivesC . contaminated fuelD . contaminating impuritie

[单选题]The lubricating oil is pumped from the drain tank, very often with （） in the suction line.A . a filterB . a strainerC . a magnetic filterD . a fine strainer