I remembered having locked the door, but I came back to .
| A．take off | B．put up | C．make sure | D．used to |
She's aiming ________ a scholarship. That is why she has been focusing her mind ________ her work.
| A．at; on | B．to; on | C．for; in | D．at; into |
Once you ______ the habit of smoking, it is hard to quit.
| A．get over | B．get into | C．get through | D．get up |
It's high time that you ________ even harder at your lessons as the exam is around the corner.
| A．work | B．will work | C．worked | D．have to work |
The center, dealing with children_______ to computer games, has achieved great success.
| A．addict | B．addicting | C．to addict | D．addicted |
—How I wish I had studied harder when I was in senior school! —If you had，you ________ a university student now.
| A．are | B．would be | C．should | D．were |