为了突出理想的远景，常在左右侧以树丛.树干.土山或建筑等加以屏障，形成左右遮挡的狭长

Do you like dogs? Do you know the following things about dogs?

The first pet dog

Dogs are meat-eating animals. They belonged to the family of wolves (狼) a long time ago. About 15,000 years ago, people started keeping wolves for hunting (狩猎). Over the time, the wolves began to look like dogs and they became people’s pets.

What a dog looks like

Dogs come in different sizes, colors and shapes, but they’re the same in some ways. All kinds of dogs have a set of forty-two strong teeth for eating. They have sharp claws (利爪) at the end of their feet for digging up soil (挖土) and holding onto the ground when they walk. They have very good eyesight. They also have high ability (能力) to hear and smell.

How a dog grows

A mother dog gives birth to one to twelve babies at a time. New-born baby dogs cannot see or hear until they are two weeks old. The mother dog gives the baby dogs milk. When they are four weeks old, they start eating soft food. When they’re eight weeks, the baby dogs have very strong legs and they can go for long walks.

How to read a dog’s feelings

Dogs act differently when they have different feelings. When a dog is angry, it opens its mouth and shows its teeth. When a dog is frightened, it lowers its ears and holds its tail (尾巴) between its legs. A happy dog always wags (摇摆) its tail.

根据短文内容，选择最佳答案。（10分）

小题1:People have started keeping dogs as pets since 　　　.

A．there were humans

B．15,000 years ago

C．there were wolves

D．the wolves looked like dogs小题2:What can the sharp claws of dogs be used for according to the passage?

A．Climbing a tree.

B．Looking for food.

C．Digging up soil.

D．Fighting against other animals.小题3:When does a dog start to eat soft food?

A．When it’s 2 weeks old.

B．When it’s one month old.

C．When it’s 2 months old.

D．When it’s 8 months old.小题4:What does a dog do when it is frightened?

A．It opens its mouth.

B．It shows its teeth.

C．It wags its tail.

D．It holds its tail between its legs.小题5:What does the passage mainly tell us?

A．Some facts about dogs.

B．The history of dogs.

C．Something interesting about dogs.

D．Dogs are human beings’ friends.

—______is the weather in Shanghai?

—______windy.[ ]

A. What ; It’s  

B. How ; It’s

C. How ; Its  

D. What ; Its

DRAPL退火炉的空燃比为（）。

A：20.11；

B：30.11；

C：30.11。

下面是关于树和线性结构的描述：

线性结构存在惟一的没有前驱的 (14) ，树存在惟一的没有前驱的 (15) ；线性结构存在惟一的没有后继的 (16) ，树存在多个没有后继的 (17) ；线性结构其余元素均存在 (18) ，树其余结点均存在 (19) 。

由此可见，由于线性结构是一个 (20) 结构，元素之间存在的是 (21) 的关系，而树是一个 (22) 结构，元素之间存在的是 (23) 的关系。

（23）处填（）。

A．首元素

B．根结点

C．尾元素

D．叶子

E．惟一的前驱元素和后继元素

F．惟一的前驱(双亲)结点和多个后继(孩子)结点

G．序列

H．一对一

I．层次

J．一对多

2013年8月，国务院已正式批准设立中国（上海）自由贸易试验区。自由贸易试验区获批推行，将使上海突破已有的条框，放宽税收、外汇使用等优惠政策，吸引更多的加工、制造、贸易、仓储物流等企业聚集，叠加中国的产业升级。中国经济的转型升级，既靠“对外开放”，又靠“对内放开”。正如加入世界贸易组织进一步激发了中国经济的活力一样，自贸试验区建设也将促进包括服务业在内的市场经济大发展。这说明（）

①投资环境改善，增强了外资来华的吸引力

②我国贸易强国的地位已经确立

③扩大市场准入，促使企业苦练内功，增强了“走出去”实力

④更好的利用国内外两个市场、两种资源，进一步扩大贸易顺差

A.②③

B.③④

C.①④

D.①③