问题
选择题
The company is quite honest and guarantees the new product ______ be under warranty for three years.
A．should
B．shall
C．will
D．can
答案
答案：B
题目分析：句意，这家公司很诚实并且保证新的产品保修期三年。这里表示给对方承诺，故用shall。
点评：情态动词有can (could), may (might), must, have to, shall (should, will (would), dare (dared), need (needed), ought to等。情态动词无人称和数的变化；不能单独使用，必须与其后的动词原形构成谓语