-Where's Tom? --He's left a _______ saying that he has something to do.
The classroom is big enough _________, but we’ll have to move if we have more students.
Green products are becoming more and more popular because they are environmentally _________.
—The sports meeting is due to be held next Monday.—_________ it rains?—Try to put it off.
Health problems are closely connected with bad eating habits and a _________ of exercise.
She was chosen to be the first secretary of the state government and has regular and immediate _________ to the president.