You must take good care of the drainage cock of the air control system. Because lead scale formed which might malfunctions the pilot control valve and other instruments.

A．the temperature

B．the rust

C．the pressure

D．the humidity

[单选题]You must take good care of the drainage cock of the air control systemBecause （） leads scale formed which might malfunction the pilot control valve and other instruments.A . the temperatureB . the rustC . the pressureD . the humidity

[单选题]Must I take a taxi? - No, you ________ . You can take my car.A.had better t

[单选题]Must I take a taxi? No, you _______. You can take a car.A.had better to.B.d

[单选题]Must I take a taxi?No, you ______.You can take my car.A.had better toB.don'

[单选题]—Must I take a taxi?—No, you____ . You can take my car.A.had better toB. do

[单选题]50．—could you take care of our dog while we are away?—__________A． With pleasureB． It's my pleasureC． Never mindD． That's all right

[单选题]If you want to teachyour children how to say sorry,you must be good at sayi

[单选题]If you want to teachyour children how to say sorry,you must be good at sayi

[单选题]If you want to teachyour children how to say sorry,you must be good at sayi

[单选题]If you want to teachyour children how to say sorry,you must be good at sayi