问题 解答题

课桌的高度比标准高度高2毫米记作+2毫米,那么比标准高度低3毫米记作什么?

现有5张课桌,量得它们的尺寸比标准尺寸长1毫米,-1毫米,0毫米,+3毫米,-1.5毫米,若规定课桌的高度最高不能高于标准高度2毫米,最低不能低于标准高度2毫米,才算合格,问上述5张课桌有几张不合格?

答案

(1)根据题意可得:比标准高度高为“+”,比标准高度低为“-”,

所以比标准高度低3毫米记作:-3毫米;

(2)根据题意得:合格的课桌的高度h范围是-2≤h≤2.

所以,不合格的课桌只有1张:+3毫米的.

阅读理解

Everyone knows that exercise is important. We all need to exercise. Doctors say it is good for us. It makes your heart and body strong. Children who often exercise are more alert(灵活). That means they do better in tests and schoolwork than those who don’t exercise.

They are many ways to exercise. You can walk, run, swim, skate, or play ball games. Make sure you exercise in the following ways: You have to like what you are doing. Exercise enough--- but not too much. It’s best to exercise twice a week. Thirty minutes each time is enough. Try all kinds of sports until you find one, two or even three sports that feel right for you.

You can exercise at fitness centers. They have a lot of equipment(设备)there. The equipment will help exercise your arms, legs and other parts of your body to make you healthy. Some people buy equipment for their homes. But it’s very expensive.

小题1:the underline word “fitness centers” in the passage means _____.

A.商务中心

B.健身中心

C.医疗中心

D.购物中心小题2:The sport “_____” is not told in the passage.

A.playing soccer

B.skateboarding

C.walking

D.running小题3:The doctors say that exercise can make your heart and body _____.

A.ill

B.happy

C.strong

D.health小题4:About “exercise”, which statement of the following is NOT right?

A.Thirty minutes’ exercise each time is enough.

B.You have to exercise too much every day.

C.You needn’t do all kinds of sports to keep healthy.

D.You have to like the sports that you are doing.小题5:It’s best to exercise _____.

A.at fitness centers

B.in groups

C.in the morning

D.twice a week

单项选择题