The news has spread all over the country _____ the spaceship succeeded in returning to the earth.
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 ______.”
“Is there a flight to London this evening?” “There _______ be. I’ll phone the airport and find it out.”