---Is there any _______ to the time about how long I can stay here?
---Yes, you must leave here before he comes back.
| A．number | B．length | C．limit | D．matter |
—I wonder what makes you a good salesperson．
—Ias a waiter for three years，which contributes a lot to my today's work．
| A．serve | B．have served |
| C．had served | D．served |
I waited for him at the train station for an hour and I was afraid that he may miss the train, but luckily, he showed up with only ten minutes．
| A．remain | B．to remain |
| C．remained | D．remaining |
The drama, “The Empress of China" that was pulled off the air for technical reasonsnow back on TV．
| A．is | B．are | C．has | D．have |
Taught in a more professional way, youthe swimming skill much better．
| A．might master | B．would have mastered |
| C．can have mastered | D．could master |
Following the decline in house prices in many small and medium-sized cities, there are now signshome prices in majors cities may also be set for a slide．
| A．which | B．that | C．how | D．what |