完型填空
Malaysia Airlines (马航) flight MH370 disappeared from radar (雷达) screens an hour after it took off on March 8.It has 1 for more than 3 months.
The plane may fall into the sea. China，Malaysia and many other countries have joined to search the 2 on the sea. The relatives of the 227 passengers and 12 crew (乘务人员) are 3 good news from them.
How did the accident 4？It is said that the plane was attacked (攻击) by the terrorists. Some think there may be something wrong with the plane，and others think the accident may be 5 by the mistake of the crew. However it is 6 to tell the reason because the plane hasn't been found yet.
It may 7 some time to find the missing plane and even more time to get to know the truth of what happened. However，we can't stop imagining what happened to the plane 8 it is found.
Whether the missing plane is found 9 not，the whole world should pay more attention to the safety of people，especially at airports.
We hope these people on the plane will be 10，and they can get together with their family members.
时，它沿斜面下滑的距离是（ ）