--- Will the new iphone cost a lot?--- I ________ think so. Apple’s products are usually expensive.

---May we go home mow ? --- No, you____. You____ to go home until 5 o’clock.

—_______ you read the words in English? —No, I can’t. They are too difficult for me.

 —Who’s that boy reading in the study ? Is it David?—It __________ be David. I saw him go home just now.

 --- Do we have to hand in our research reports this afternoon, Professor Smith?--- Yes, you _______ . I will be waiting to check them all the afternoon.