Some aspects of a pilot's job      be boring, and pilots often      work at inconvenient hours．

–I’ve taken someone else’s green sweater by mistake.–It       Harry’s. He always wears green.

You________ drink it, for it is poisonous.

---Must I hand in my exercise book now, Mr. Zhao?---No, you ______. You may give it to me tomorrow.

Living in a fast-paced world, we                  get left behind if we stop learning.