_______ I went to the South Lake in Hanzhong, I was deeply impressed with its beautiful scenery.
| A．For the first time | B．The first time |
| C．At first | D．It was the first time |
It was such a difficult problem_______ few students in our class worked out．
| A．that | B．what | C．as | D．which |
—What do you mean by saying money makes money?
—______, the more you invest, the greater your potential profit will be．
| A．To be honest | B．To begin with |
| C．To tell you the truth | D．To put it another way |
The first time I saw her, Mary was standing still in the wind, her long hair _____in the air.
| A．is flying | B．flying | C．to fly | D．flew |
Sometimes he found _______very hard to fall asleep at night, so he went to see the doctor．
| A．him | B．this | C．that | D．it |
—What’s that noise? Is the water still running?
—Oh, my god! I ________to turn it off after I brushed my teeth．
| A．was forgetting | B．forgot | C．had forgotten | D．am forgetting |