—Where did you find our chemistry teacher?
—It was in the lab ______ he was doing his experiment.
| A．that | B．where | C．which | D．in which |
---It’s cloudy outside. Please take an umbrella.
--- ______.
| A．Yes, take it easy | B．Well, It just depends |
| C．OK, just in case | D．All right , you’re welcome |
With so many people ____ the Internet, it is difficult to see online movies at the same time.
| A．surf | B．to surf | C．surfing | D．surfed |
He hurried to the station, ____ to catch the last train.
| A．to hope | B．hope | C．hoping | D．hoped |
---Why do you think he can succeed?
---He believes in himself, ____ is the most important, I think.
| A．which? | B．what | C．that | D．who |
What should you say when ___ to a stranger?
| A．to introduce | B．introducing | C．introduced | D．being introduced |