—Is Jack on duty today?—It________ be him. It’s his turn tomorrow.
In my opinion, work provides us much ________ just salary and income; it also helps us realize our dreams and makes us feel confident.
The teacher set such difficult problems ______ nobody could work out _____ none of us passed the test.
The doctor insisted that the patient_______seriously ill and that an operation_______in no time.
It _____ every day so far this month. I can’t tell you if it _____ tomorrow.
The most crowded part in a city is usually the city center, ______ many shopping malls and office buildings.