Her husband had ____ a large business during his lifetime.
| A．built up | B．checked out | C．picked out | D．gone through |
--- How was the televised debate last night?
--- Super! Rarely ______ so much media attention.
| A．a debate attracted | B．did a debate attract |
| C．a debate did attract | D．attracted a debate |
With the help of high technology, more and more new substances ______ in the past years.
| A．discovered | B．have discovered |
| C．had been discovered | D．have been discovered |
--- Guess what! I have got A for my term paper.
--- Great! You ______ read widely and put a lot of work into it.
| A．must | B．should | C．must have | D．should have |
--- Did you tidy your room?
--- No, I was going to tidy my room but I ______ visitors.
| A．had | B．have | C．have had | D．will have |
Alan is a careful driver, but he drives ______ of my friends.
| A．more carefully | B．the most carefully | C．less carefully | D．the least carefully |