I can still remember that it is since the 1990’s, _____ we began to use cell phones,_______ the number of mobile users has greatly increased．
| A．while; when | B．when; what | C．before; that | D．when; that |
I decided to pay a visit to my former teacher as soon as I ____.
| A．finish what I did | B．finished what I did |
| C．would finish what I was doing | D．finished what I was doing |
. I like getting up very early in summer. The morning air is so good _________.
| A．to be breathed | B．to breathe |
| C．breathing | D．being breathed |
. My English teacher’s humor was _________ make every student burst into laughter.
| A．so as to | B．such as to |
| C．such that | D．so that |
I feel greatly honored _________ into their society.
| A．to welcome | B．welcoming |
| C．to be welcomed | D．welcomed |
—Did the book give the information you needed?
—Yes. But _________ it, I had to read the entire book.
| A．to find | B．find |
| C．to finding | D．finding |