we can save electricity ______ lights when we leave the room A by not turning off

we can save electricity ______ lights when we leave the room A by not turning off
B by turning off C by not turning on D by turning on
Please remember _____ your teeth before you go to bed
A washing B wash C brush D to brush
The baby will cry if you _____ his toys
A put out B take off C turn on D take away
The Oriental Pearl TV Tower is one of the tallest _____ in the world
A buildings B build C built D building
If there is no rain,there_____ no water to drink
A will be B be C is D have
People can only live _____ three days without water
A in B in about C about D for about