--Steven has got the first prize in the math contest. --____ he looks so happy today.
— Write to me when you get home. — __________.
I was really anxious about you. You _______ home without a word.
“Did Jim come?” “I don’t know. He _______ while I was out.”
“Look at these tracks. It _______ be a wolf.” “Don’t be so sure. I think it _______ be a fox.”
“Show me your permit, please.” “Oh, it’s not in my pocket. It ______.”