With the development of high technology, more and more new things _______ to the field of IT．
| A．have introduced | B．are being introduced |
| C．were introduced | D．had been introduced |
It doesn’t matter how much loss we have suffered; just avoid _____ the mistake again.
| A．to make | B．being made | C．having made | D．making |
Just as sound travels through the air in waves, electricity travels through the air in ______ radio waves.
| A．what is called | B．which is called | C．what it is called | D．which it is called |
It was _____ of Jack to turn off the radio when I was sleeping in the bedroom.
| A．considerable | B．considerate | C．disturbing | D．sensible |
A student will be immediately dismissed if he/ she is found _____ in school.
I failed again in the exam and only then _____ how much time I had wasted.
| A．I realized | B．did I realize | C．I had realized | D．had I realized |