Although his experiments were designed to support the ideas the influence of environment upon plants, Mendel found that many characteristics were passed on from one generation to the next.
| A．concerning | B．attaching to | C．involving in | D．concerning with |
More and more high-rise buildings have been built in big cities ______ space．
| A．in search of | B．in place of |
| C．for lack of | D．for fear of |
---We haven’t seen each other for ages．
---No, I don’t remember how many years ago _______ I last saw you．
| A．it was that | B．was it that |
| C．it was when | D．was it when |
We are still at the airport．If it weren’t for the delayed flight, we _______ the concert right now．
| A．can be enjoying | B．must have enjoyed |
| C．would be enjoying | D．should have enjoyed |
_____ his research paper, Professor Reagan experienced various hardships and loneliness for nearly half a year．
| A．Accomplishing | B．To accomplish |
| C．Accomplished | D．Having accomplished |
____ the flight to New York will be delayed is _____ I’m especially worried about．
| A．When; what | B．Whether; that |
| C．When; that | D．Whether; what |