________ you’ve heard the song, you’ll never forget it.
| A．At once | B．Once more |
| C．Once upon a time | D．Once |
—Why did you leave the water running in the sink?
—My goodness! I guess I ____ to turn off the tap．
| A．forgot | B．have forgotten | C．forget | D．had forgottten |
Washington, a state in the United States, was named _____ one of the greatest American presidents．
| A．in favor of | B．by means of ． | C．in honour of | D．in spite of |
____ you ask many different questions will you acquire all the information you need to know．
| A．If only | B．As far as | C．So long as | D．Only if |
Have you ever wondered why some of the smartest students in your class sometimes ____ failing exams?
| A．take up | B．pick up | C．come up | D．end up |
The minister stressed that under no circumstances ____ the disabled to be looked down upon．
| A．is | B．are | C．has | D．have |