Email, as well as letters, ______ an important part in daily communication.
| A．is playing | B．have played | C．are playing | D．play |
I wonder whether this student has ______ it takes to be a music major.
| A．what | B．how | C．which | D．when |
–A boy was killed by the tiger in the zoo.
–He was believed ______ into the cage while feeding the tiger without permission.
| A．to fall | B．to be falling | C．to have fallen | D．having fallen |
As the most acute one in _______ history of all epidemics, the Spanish Flu had ______ tendency to strike the young and fit rather than the old.
| A．不填；the | B．不填; a | C．the; 不填 | D．the; a |
Billionaires Bill Gates and Warren Buffett asked American billionaires to ______ at least half of their wealth to charities.
| A．take away | B．give away | C．take up | D．give up |
I feel proud to be born into a family ______ education is highly valued.
| A．where | B．that | C．which | D．who |