骶管裂孔除以骶角作为定位标志外，还可以_______分别为A和B点，________

根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为多余选项。

Laughter and tears are part of living. But do you find enough time for laughter? I am not

asking if you experience lots of good times. Of course we should laugh during the happy times.

1  

Erma Bombeck is known for her humorous books, but she wrote one that covered a more

serious topic: cancer in children. Erma talks with lots of children with cancer and learns an important life lesson from them.   2  

She tells the experience of 15-year-old Jessica from Burlington, VT. Jessica’s leg was amputated (锯掉) at the knee because of cancer. Jessica tells about playing soccer. She kicked the ball hard and it flew off in one direction while her artificial leg flew another way. Then “the tall, pretty person that I am,” she said, “sat on the floor in laughter.”

Jessica may not have laughed about her cancer, but she laughed about dealing with its results.  3  

Then there is the story of 17-year-old Betsy. She made her way to the radiation room(放射室) for

her regular radiation therapy. As usual, she dropped her hospital coat and, wearing only her birthday suit, climbed onto the table and waited. After a couple of moments she began to realize something disturbing: the extra people in the room were not the medical students she had thought, but rather painters giving an estimate on painting!    4  And like Jessica, her ability to laugh helped her to deal with one of the most difficult things a young person can endure(忍受) — cancer.

There is a time to weep and a time to laugh.    5   And you’ll smile at the end.

A．She was learning to wear an artificial leg.

B．And her laughter helped her cope.

C．You would be happy if you find reasons to laugh.

D．Betsy laughed heartily about the incident.E. But do you also laugh during the difficult times?

F. If you can laugh even when the going gets rough, you’ll make it.

G. She learns that all cancer survivors prefer to laugh.

（4分）如图为某同学在“研究匀变速直线运动”的实验打出的纸带的一部分，其中A、B、C为三个计数点，已知此物体做匀变速直线运动，打点计时器使用50Hz的交流电，测得AB=3．27cm，AC=8．00cm，则物体的加速度a=           m／s。

简述如何针对不同气质的学生进行因材施教。

在Java程序中，通过类的定义只能实现单重继承，但通过【 】的定义可以实现多重继承关系。

夏季蔬菜覆盖遮阳网有什么优点？