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The medical research shows eating too much fat can_________ heart disease and blood pressure, so you must be more careful with your diet.
| A．contribute to | B．refer to | C．attend to | D．devote to |
After living with his grandparents in the countryside for ten years, the boy returned to the big city ____ his parents worked.
| A．which | B．where | C．that | D．when |
— ____ can I deal with such a situation?
— Take ____ measure you think best.
| A．How; whichever | B．What; whatever |
| C．How; whatever | D．What; whichever |
____ it will do us harm or good remains to be seen.
| A．If | B．Whether | C．That | D．Where |
The river, ____ are covered with trees, is very long.
| A．which banks | B．of which banks |
| C．whose the banks | D．the banks of which |
He is rather difficult to make friends with, but his friendship, ____, is more true than any other.
| A．once gained | B．when to gain |
| C．after is gained | D．while gaining |