—Can I call you back at two o’clock this afternoon?
—I’m sorry, but by then I______ to Beijing. How about five?

—Has your son come back from abroad for the winter vacation?
—Yes. But he stayed at home for only a week. Now he      back to college.

The ambulance was just arriving, for a worker, who ______ the window on the second floor, fell off the window.

---Are you still busy?---Yes, I ____ my work, and it won’t take long.

The first decade of the 21st century ______ breathtaking, non-stop development in China．

The letters for the boss___________ on his desk but he didn’t read them until 3 days later.

She said the contest ________ by the Students’ Union the next Friday.

It was the first time that I _______ visitors since I’d moved to London.

---Has Ingid handed in her paper yet?
---I’m not sure. She _______ on it last week.

No one can tell how many sufferings the kidnapped boy ________ when he was rescued yesterday.