It is five years since my dear aunt __________ here.
| A．left | B．has left | C．is left | D．had left |
I __________ the Palace Museum with my grandparents the other day.
| A．was visiting | B．have visited |
| C．visited | D．am visiting |
— We can use QQ to talk with each other on the Internet.
— Really? Will you please show me __________ it.
| A．what to use | B．how to use |
| C．when to use | D．where to use |
Many families have their own cars. __________， it causes the terrible air problem.
| A．Because | B．If | C．However | D．For |
— Hello! Remember me?
— I seem to have met you __________.
| A．before | B．ago | C．since | D．some time |