【C5】A．remainB．increaseC．decreaseD．vary

【40】A．remainB．leaveC．remainedD．left

【C15】A．remainB．keepC．makeD．cause

A．reduceB．increaseC．produceD．consume

【C20】A．riseB．increaseC．trendD．presence

The operation could ____her life by two or three years.A．prolongB．increaseC．expandD．contin

【C9】A．remain stableB．increaseC．keep changingD．decrease