问题 问答题

很早的时候,我们祖先就注意观察天象,商朝甲骨文里有许多日食、月食的记载,如图所示.近年,我国科学家根据古书中“(周)懿王元年天再旦于郑”的记载,猜想“天再旦”是天亮了两次,即发生在早晨日全食.恰巧,1997年3月9日,我国境内发生了20世纪最后一次日全食.日全食发生时,新疆北部正好是天亮之际.这次日全食的观察,证实了我国科学家对“天再旦”的猜想,为我国“夏商周断代工程”的课题研究提供了重要的依据.经过推算,我国科学家得出周王元年是公元前899年.日全食现象可以用______来解释.科学家们在这次研究中采用了多种科学方法,请你任意写出两种:______.

答案

(1)日食现象是光的直线传播形成的,发生日食时,月球在地球和太阳之间,它们在一条直线上,射向地球的光被月球挡住了;

(2)短文中涉及的科学方法有:

猜想:猜想“天再旦”是天亮了两次,即是发生在早晨的日全食

观测:日全食发生时,新疆北部正好是天亮之际.这次日全食的观测…

推算:经过推算,我国科学家…

验证:为我国“夏商周断代工程”的课题研究提供了重要的依据

故答案为:光的直线传播;猜想;观测;(或推算、验证等).

单项选择题
阅读理解

Long bus rides are like television shows. They have a beginning, a middle, and an end with commercials (商业广告) thrown in every three or four minutes. The commercials are unavoidable. They happen whether you want them or not. Every couple of minutes a billboard glides by outside the bus window. “Buy Super Clean Toothpaste.” “Drink Good Wet Root Beer.” “Fill up with Pacific Gas. “Only when you have fallen asleep, which is equal to turning the television set off, can you get separated from the unending cry of “You Need It! Buy It Now!”

As for the ride itself, the beginning of it is comfortable and somewhat exciting, even if you’ve traveled that way before. Usually some things are keeping changing out of the windows — various houses, crop fields, attractive bridges, … and sometimes even a small accident. Your bus driver may have a unique style of driving and it’s fun trying experience it the first hour or so. If the driver is particularly reckless (鲁莽的) or daring, the ride can be as thrilling (惊心动魄的) as an adventurous story. Will the driver pass the truck in time? Will the driver move into the right or the left hand lane? After a while, of course, the excitement dies down. Sleeping for a while helps pass the middle hours of the ride. Food always makes bus rides more interesting. But you’ve got to be careful of what kind of food you eat. Too much salty food can make you very thirsty between stops.

The end of the ride is somewhat like the beginning. You know the riding will soon be over and there’s a kind of expectation and excitement with that. The seat, of course, has become harder for the hours having passed. By now you may sit with your legs crossed, or with your hands in your lap, or with your hands on the arms, or even with your hands crossed behind your head. That is to say that the end comes just at no more ways to sit.

小题1:According to the passage, what do the passengers usually see when they are on a long bus trip?

A.Buses on the road.

B.Films on television.

C.Advertisements on the billboards.

D.Gas stations.小题2:What is the purpose of this passage?

A.To give the writer’s opinion about long bus trips.

B.To persuade you to take some long bus riding.

C.To explain how bus trips and television shows differ.

D.To describe the billboards along the road.小题3:The writer of this passage would probably prefer ______.

A.those reckless bus drivers

B.driving with no one around

C.a television set on the bus

D.no billboards along the road小题4:The writer feels long bus rides are like TV shows because ______.

A.the commercials both on TV shows and on billboards along the road are fun

B.they both have a beginning, a middle and an end, with commercials in between

C.the drivers are always reckless on TV shows just as they are on buses

D.both traveling by bus itself and watching TV programs on bus are not exciting.小题5:The writer thinks that the end of the ride is somewhat like the beginning because both are .

A.exciting

B.comfortable

C.tiring

D.boring