People use metal for making machines. （变为被动语态）

Metal ____  ____ for making machines.

    Unwanted tires can be a fire threat．People who like to set fires often start a large hill of tires

burning．Some tires buried with other waste materials under town of dirt (unclean matter) may become uncovered．When this happens, the tires can trap water．They may become a home for insects or small animals that carry disease.

    Unlike many products, tires are built to last a long time．They do not break down easily．Tires are made of strong rubber．The rubber is strengthened by metal wires or other man- made material.

    Some tires that are still safe for road use can be repaired by companies that produce tires．The repaired tires can be put back on cars and driven safely for many more kilometers.

    However, many used tires cannot be repaired．In some areas, they are collected and given to companies that re - use them．The recycling companies have machines that melt down or rip tear with force the tires．The remaining particles then are used to make other products.

    Some rubber products made from recycled tires include asphalt (沥青) used to cover streets or play areas for children．Other recycled material can be used to produce chemical additives (添加剂) that help grass grow in open - air sports centers.

1．The reason why used tires should be recycled is that ________.

A．insects living in room in used tires may spread disease

B．used tires piled together may cause a fire if lighted

C．used tires should be made good use of and changed into useful material

D．people are too poor to buy new ones

2．The population of the United States may be ________.

A．290,000,000

B．480,000,000

C．250,000,000

D．120,000,000

3．Now, we can recycle used tires by means of ________.

A．repairing

B．reusing

C．making other products

D．all above

4．The underlined word ‘threat’ means ________.

A．fact

B．hidden danger

C．cause

D．warning

5．The title of the passage is ________.

A．Used Tires Are Dangerous in Many Countries

B．Used Tires Are Increasing in the World

C．Recycling Used Tires

D．People Are Working at Ways to Deal with Used Tires

    Unwanted tires (轮胎) from cars and trucks are increasing worldwide．In the United States more than two- hundred - forty million of the rubber wheel coverings are thrown away each year．That is about one used tire for every person living in the country.

    Unwanted tires can be a fire threat．People who like to set fires often start a large hill of tires

burning．Some tires buried with other waste materials under town of dirt (unclean matter) may become uncovered．When this happens, the tires can trap water．They may become a home for insects or small animals that carry disease.

    Unlike many products, tires are built to last a long time．They do not break down easily．Tires are made of strong rubber．The rubber is strengthened by metal wires or other man- made material.

    Some tires that are still safe for road use can be repaired by companies that produce tires．The repaired tires can be put back on cars and driven safely for many more kilometers.

    However, many used tires cannot be repaired．In some areas, they are collected and given to companies that re - use them．The recycling companies have machines that melt down or rip tear with force the tires．The remaining particles then are used to make other products.

    Some rubber products made from recycled tires include asphalt (沥青) used to cover streets or play areas for children．Other recycled material can be used to produce chemical additives (添加剂) that help grass grow in open - air sports centers.

1．The reason why used tires should be recycled is that ________.

A．insects living in room in used tires may spread disease

B．used tires piled together may cause a fire if lighted

C．used tires should be made good use of and changed into useful material

D．people are too poor to buy new ones

2．The population of the United States may be ________.

A．290,000,000

B．480,000,000

C．250,000,000

D．120,000,000

3．Now, we can recycle used tires by means of ________.

A．repairing

B．reusing

C．making other products

D．all above

4．The underlined word ‘threat’ means ________.

A．fact

B．hidden danger

C．cause

D．warning

5．The title of the passage is ________.

A．Used Tires Are Dangerous in Many Countries

B．Used Tires Are Increasing in the World

C．Recycling Used Tires

D．People Are Working at Ways to Deal with Used Tires