问题 选择题
已知
a
b
为两个单位向量,下列四个命题中正确的是(  )
A.如果
a
b
平行,那么
a
b
相等
B.
a
b
相等
C.如果
a
b
平行,那么
a
=
b
a
=-
b
D.
a
b
共线
答案

a
b
为两个单位向量,

∴如果

a
b
平行,那么
a
=
b
a
=-
b
,故A不正确,C正确;

因为两向量相等的充要条件是模相等且方向相同,所以B不正确;

a
b
为两个单位向量,

a
b
为两个向量不一定平行,故D不正确.

故选C.

选择题
阅读理解

Several years ago, I worked as a truck driver for a company. On Saturdays I usually spent several hours doing something to keep my truck in good condition.

One Saturday, as I was cleaning my truck, I noticed the boss’s elderly father came out to ask his grandson to take him fishing after work. The grandson told him all about how much he would love to do that, but he just couldn’t because he had other plans already. The old man hobbled (蹒跚) off to the house.

Then I heard the grandson telling his dad, "I’m not taking that old man fishing! It’s worse than taking a kid."

That just broke my heart.

I quit working immediately and went home to fetch my fishing gear (渔具) and a chair. Then I came back and invited the old man to go fishing. He accepted happily.

When we got to the river, I let him sit in the chair at the edge of the water. It wasn’t long before he got a fish. He got one fish after another. His eyes were shining like a child. About half an hour later, he told me he was tired and needed to go home. So I took him and the fish home.

Two weeks later, the old man died. His family told me later that all he talked about during that time was his fishing trip. I am satisfied that I have taken an old man on his last fishing trip, but I am sorry that his family have lost their last chance. Whenever you get the chance, don’t forget about taking Grandpa fishing. Someday, you may be in the same place and you’ll want your family to care about you, too.

小题1:The writer wrote the passage mainly to ________.

A.tell us something about his work

B.tell us about a fishing experience

C.persuade us to take Grandpa fishing

D.persuade us to care about the elderly小题2:The old man’s Grandson refused to fish with him because ______.

A.he had something more important to do that day

B.he didn’t like to fish with an old man

C.he was tired of his job and he wanted to rest

D.he preferred fishing with a child小题3:What’s the possible meaning of the underlined word "quit"?

A.start

B.stop

C.imagine

D.try小题4:According to the passage, we can infer(推断) that the author is _______.

A.willing to make his boss happy

B.in need of care from his family

C.prefers fishing to his work

D.kind and warm-hearted