When asked why he prefers bikes to buses, the professor said,  “Riding a bicycle takes __________ half an hour, but it’s more convenient and environmentally friendly. ”

Up to now, Hope Project has helped thousands of students who would       have dropped out of school.

One of the greatest benefits of Internet friendships is that they are based on common interests, ________ appearance, age or popularity.

Mike was usually so careful, ______this time he made a small mistake.

— So you missed the meeting．— ______. I got there five minutes before it finished.