--- My son is lost. Did you see a boy pass by here? --- I saw ______ boy hidden behind ______ tree over there. You may go and have a look.
-----Hi, Peter. Long time no see. -----Oh, it’s you, Jack. I’m sorry I didn’t ________you at first.
________its low cost, the appeal of iron as a building material lies in its strength, its resistance to fire, and its potential to span long distances.
When you rewrite the paragraph, I advise you to______ the last sentence as it is rather misleading.
John, look at the time! _____you play the piano at such a late hour?
---I prefer shutting myself in and listening to music all day on Sundays. ---That’s _______ I don’t agree. You should have a more active life.