— Is it for two months ________ they have stayed here?
— No. It’s only three weeks ________ they arrived here.
| A．that; since | B．that; after | C．since; before | D．when; that |
If you want to sell your product you must _____ it.
| A．advertise | B．advertise for | C．advertise on | D．advertise to |
Are the parents who let their child who is ______ walk in the dark alone at night considerate?
| A．young enough | B．too young to | C．not old enough to | D．so young |
The telephone,but by the time I got indoors, it stopped.
| A． | had rung | B． | was ringing | C． | rings | D． | has rung |
It is fairly common in Africa for there______ a group of expert musicians surrounded by others who also join in the performances.
| A．being | B．to be | C．be | D．is |
I_____ violin lessons every two weeks, but I think I ‘ll make it every week from next month.
| A．am having | B．have had | C．have | D．have been having |