---Tom, _____we go home together this afternoon ? ---Ok !

So far no life has been found outside the earth, but while some scientists are actively searching for living things in outer space, others firmly believe there ____ . 

The teacher recommended that everyone _______ this dictionary.

Generally speaking, my grandmother is nice and kind, but she _______ be very stubborn at times.

(2013·东北三校4月二次联考)No matter how healthy you ________ be, you need to consult a doctor from time to time.