______ of the earth’s surface ______ covered with water. A Two-third; is B Two-third; are C Two-thirds; is D Two-thirds; are
__________ in watching the car passing by that he didn't notice his friends.
In the United States, the black people on the whole __________ ahigh unemployment rate.
I tried my best to make this speech but many listeners __________ laughing as soon as I began.
I quarreled with my sister yesterday, but now I have already __________ with her.
Volunteers are always ready to help others and never want to ask for anything __________.