There is still a strong argument ________ mobile phones are a particular risk to children.
| A．when | B．which |
| C．that | D．what |
Most experts agree that washing hands regularly is a ______way to prevent the spread of many diseases.
| A．powerful | B．illegal | C．painful | D．awful |
He suggested that we should _______ the instruction.
| A．simple | B．simplify | C．simply | D．simplified |
Spectators of horse racing come primarily to ________ the result of each race.
| A．predict | B．gamble | C．bet | D．bet upon |
The NBA ______ of having the best basketball players in the world/
| A．praises | B．boasts | C．claims | D．prides |
The plan was that the two parties should first reach an agreement on the basic ______, the details to be worked out later.
| A．standard | B．practice | C．habit | D．principle |