我国的印刷技术演变成金属活字版印刷技术是在( ) A．13世纪中叶 B．14世纪

阅读理解。

       Some friends come into our lives for just a short time. Others come and stay forever. Think about

   your closest friends. How long have you known each other? Some people say that their spouse

  (husband or wife) or family member is their best friend. Others say they have known their closest friends

  for many years. And some great friends haven't known each other all that long, but knew right away that

  there was a connection (联系) between them. Could it be that there is a twin spirit out there for each of

  us?

       What turns a stranger or acquaintance (熟人) into a friend? Do you know right away if you are going

  to like someone? Some people think that any stranger can become a friend if they spend enough time

  together. That may be true for some people. But one thing most of us agree on is that true friendships

  seem to happen when people have something in common. Perhaps we see a part of ourselves iii our

  friends; Maybe seeing the good in them helps us to see the good in us as well.

1. What's the main idea of the first paragraph?

A. Friendship lies only between friends or family members.

B. Friendship is a connection between friends and family members.

C. Friendship is one mind in two bodies.

D. Friendship between the closest friends lasts until they have a twin spirit.

2. What idea can we get from the second paragraph?

A. Most friends have similar likes and dislikes.

B. Your friend is the man who knows all about you,and still likes you.

C.It's easy to turn a stranger into a good friend.

D. True friendships mean to share everything with your friends.

如图所示是一列简谐横波在某一时刻的图象，A、B、C是介质中的三个质点．已知波是向x正方向传播的，波速为v=20m/s，下列说法中正确的是（　　）

A．这列波的波长是10m

B．质点A的振幅为零

C．质点B此刻向y轴正方向运动

D．质点C再经过0.1s通过平衡位置

可治疗高血压的药物（）

A、去甲肾上腺素

B、麻黄碱

C、间羟胺

D、普萘洛尔

E、苯肾上腺素

（）是我国乃至东南亚地区最大的中新生代化石保护区。

A.云南澄江动物群化石

B.四川自贡恐龙化石

C.山东山旺古生物化石

D.北京及自然博物馆

未经监理工程师许可，不得对基坑进行回填。一般要到结构物的拆模期终了（）之后进行回填。如果养生条件反常，应按监理工程师的指示延长时间。

A.2d

B.3d

C.1d

D.5d