It’s impossible_____ such a little boy_____ the week.[ ]

Peter has good grades in all his subjects, but he never shows off.—-I agree. He is very ________.

_____do you sleep every night? —Six to eight hours.[ ]

We work together to achieve our common purpose: __________ world that is safer, cleaner and healthier than __________ one we are living in.

Is this ________ key, Tom? —No, that one is ________.