油炸食品放凉超过（）小时后，或冰箱冷藏的油炸食品，食用前要重新彻底加热。
A、1
B、2
C、3
D、4
参考答案：C
正方形的面积和边长成正比例。[ ]
She is a wellknown doctor now, but she ________ as a cleaner at the hospital for five years.
A．has worked
B．worked
C．had worked
D．works
