下列说法不正确的是（ ） A．位似图形一定是相似图形 B．相似图形不一定是位似图形

有关心境障碍的混合发作是指（）

A.抑郁发作和躁狂发作交替出现

B.既往有抑郁发作，本次为躁狂发作

C.既往有躁狂发作，本次为抑郁发作

D.躁狂症状和抑郁症状在一次发作中同时出现

E.抑郁发作和躁狂发作之间的快速转换

如果表达式--X+y中，--是作为成员函数重载的，+是作为成员函数重载的，则该表达式还可为（ ）。

A．将继承这个类的所有行为

B．子类将自动成为监听器

C．不必实现任何不需要的WindowListener方法

D．为了层次清楚，美观大方

Using too much water or throwing rubbish into our rivers are clear ways that humans can put our water supply in danger , but we also affect our water supply in less obvious ways. You may wonder how paving(铺砌) a road can lead to less useable fresh water. A major part of the water we use every day is groundwater. Groundwater does not come from lakes or rivers. It comes from underground. The more roads and parking lots we pave the less water can flow into the ground to become groundwater.

Human activity is not responsible for all water shortages(短缺). Drier climates are of course more likely to have droughts(干旱) than areas with more rainfall, but in any case, good management can help to make sure there is enough water to meet our basic needs.

Thinking about the way we use water every day can make a big difference, too In the United States , a family of four can use 1. 5 tons of water a day! This shows how much we depend on water to live, but there’s a lot we can do to lower the number.

You can take steps to save water in your home. To start with use the same glass for your drinking water all day. Wash it only once a day. Run your dishwasher (洗碗机)only when it is full 。Help your parents fix any leaks in your home. You can even help to keep our water supply clean by recycling batteries instead of throwing them away.

小题1:Which of the following is most likely to lead to less groundwater?

A．Using river water.

B．Throwing batteries away.

C．Paving parking lots.

D．Throwing rubbish into lakes.小题2:What can be inferred from the text?

A．All water shortages are due to human behavior.

B．It takes a lot of effort to meet our water needs.

C．There is much we can do to reduce family size.

D．The average family in America makes proper use of water.小题3:The last paragraph is intended to             .

A．show us how to fix leaks at home

B．tell us how to run a dishwasher

C．prove what drinking glass is best for us

D．suggest what we do to save water at home小题4:The text is mainly about          .

A．Why paving roads reduces our water

B．how much we depend on water to live

C．why droughts occur more in dry climates

D．how human activity affects our water supply

以一般贸易方式进口的货物就是一般进出口货物。 ( )

下列说法中正确反映思维与存在的关系何为第一性的是（）

①原子是世界的本原

②宇宙是由元气构成的物质实体

③宇宙便是吾心，吾心便是宇宙

④揠苗助长

A.①②

B.②④

C.②③

D.①④