It is Jack as well as his wife that is ______ for their son’s bad performance at school.
The fact that people are afraid to go out at night is often a result of perceived (感知) danger ________actual danger.
In Hangzhou, Mr. Black was so struck ______ the beauty of nature that he stayed ________ another night.
.It is morning _____ we have four classes, not afternoon.
Mother told Jim to watch the milk until it boiled and then _________ off the gas.
The idea puzzled me so much that I stopped for a few seconds to try to _______.