---- Which city will be host city for the next Olympic Games?
---- London.
| A．a | B．/ | C．the | D．an |
The new research team was led by the ________engineer.
| A．main | B．major | C．chief | D．primary |
—Will you come?
—________you promise not to invite Mary.
| A．As if | B．If only | C．Only if | D．Even if |
They ________ to enter the building by the back door; however, the front door was locked.
| A．are supposed | B．aren’t supposed | C．weren’t supposed | D．were supposed |
He _________his friend in the crowd at the first sight and called out his name.
| A．spotted | B．watched | C．observed | D．glared |
Used to TV shows, ________ everything is quick and entertaining, many people do not have the patience to read a book that requires thinking．
| A．which | B．what | C．where | D．when |