Would you please tell me_______ to do with all the problems, Mr. Chen — No problem.

“The day is coming ________ telegraph wires will be laid on to houses like water or gas.” Bell wrote to his father.

Most of the mistakesbecause of carelessness.

New York is referred to as a melting-potbecause its citizens comefromcultures.

Armstrong became interested in _______ ever since he took his first _______ at the age of six.