用所给词的适当形式填空。

1. When spring _____ (come),the animals which sleep in winter start waking up.

2. Our manager _____ (go) to Paris on business already and he will be back in a few days.

3. The Eiffel Tower _____ (design) by a Frenchman called Gustave Eiffel over 100 years ago.

4. While we _____ (travel) in Australia last summer, I visited Lucy who once taught English in our school.

5. The suspect denied _____ (steal) the valuable painting before the witness appeared.

6. We will have no water to drink or use if we  _____ (not stop) wasting it now.

7. The world's first great nurse Nightingale's birthday _____ (become) International Nurses' Day in 1974.

8. Scientists _____ (study) the global warming for several years. They are working hard to find a solution.

9. I'm sorry I didn't hear you because I _____ (listen) to music.

10. The Conference on Poverty Reduction (扶贫大会) _____ (hold) in Shanghai in May, 2004.

下列成本的大小与距离有关的是（）

A.运输成本

B.资本成本

C.信息成本

D.决策成本