Losing a baby tooth can be fun for a kid. You can put it under your pillow and look forward to finding some money there in the morning. And then you can watch your new permanent(永恒的) tooth grow in its place.

But if a permanent tooth falls out, that’s a problem. There isn’t another one under the gum(齿龈)that can replace it. Unfortunately, this happens to some older people. And if permanent teeth fall out or need to be pulled, an older person might need dentures.

Dentures, known as false teeth, are a set of replacement teeth for any teeth that are missing. There are partial dentures, which take the place of only a few teeth and prevent the others from changing position. If all the teeth are gone, the person would need complete dentures, which replace every tooth in the mouth.

Dentures can cause pains at first and take little time to get adjusted to. They also need special care. They should be brushed daily with a special denture brush and cleanser and soaked（浸泡） in denture solution when not in the mouth.

Dentures are important for the old because, without teeth, it’s hard to smile, talk, and eat properly. But it can be a little weird if you see someone take out his or her dentures. It can also be strange to see someone, like a grandparent, without dentures in because he or she won’t have any teeth. Try not to make fun of the person because this could cause hurt feelings.

People usually lose their permanent teeth due to periodontal disease（牙周炎）, or gum disease, which is caused by bacteria that attacks the gums. Diseased gums aren’t strong and healthy, so teeth can get loose and fall out. Older people often have many cavities(洞)that have been filled over the years, and these fillings can weaken over time, leading to more tooth problems.

 If one of your baby teeth falls out, you      .

A．should have a false tooth fixed in its place  B．have to put it under your pillow at once

C．will gain a permanent tooth in future        D．can exchange it for some money

【小题２】A person wearing dentures      .

A．should brush them with a special denture brush every few days

B．will take a very long time to adjust himself or herself to them

C．will experience unpleasant feelings at the beginning of fixing them

D．should use denture solution to soak them in his or her mouth

【小题３】Which of the following is NOT true according to the passage?

A．Partial dentures can prevent the remaining teeth from changing position.

B．Old people will find it hard to smile, talk, and eat properly without teeth.

C．A person’s teeth will possibly get loose if diseases strike his gums.

D．It is hard for a person to wear dentures if all his teeth have fallen out.

【小题４】What does the underlined word “weird” mean in the fifth paragraph?

A．inconvenient           B．excited                 C．uncomfortable       D．impolite

Losing a baby tooth can be fun for a kid. You can put it under your pillow and look forward to finding some money there in the morning. And then you can watch your new permanent(永恒的) tooth grow in its place.

But if a permanent tooth falls out, that’s a problem. There isn’t another one under the gum(齿龈)that can replace it. Unfortunately, this happens to some older people. And if permanent teeth fall out-or need to be pulled-an older person might need dentures.

Dentures, known as false teeth, are a set of replacement teeth for any teeth that are missing. There are partial dentures, which take the place of only a few teeth and prevent the others from changing position. If all the teeth are gone, the person would need complete dentures, which replace every tooth in the mouth.

Dentures can cause pains at first and take some time to get adjusted to. They also need special care. They should be brushed daily with a special denture brush and cleanser and soaked in denture solution when not in the mouth.

Dentures are important for older folks because, without teeth, it’s hard to smile, talk, and eat properly. But it can be a little weird if you see someone take out his or her dentures. It can also be strange to see someone, like a grandparent, without dentures in because he or she won’t have any teeth. Try not to make fun of the person because this could cause hurt feelings.

People usually lose their permanent teeth due to periodontal disease, or gum disease, which is caused by bacteria that attacks the gums. Diseased gums aren’t strong and healthy, so teeth can get loose and fall out. Older people often have many cavities(洞)that have been filled over the years, and these fillings can weaken over time, leading to more tooth decay(腐烂).

1.If one of your baby teeth falls out, he or she       .

2.A person wearing dentures      .

3.Which of the following is NOT true according to the passage?

4.What does the underlined word “weird” mean in the fifth paragraph?

 The huge Florida wetland known as the Everglades is a slow-moving river 80 kilometres wide but only a few centimeters deep. People call the Everglades a “river of grass” because sawgrass covers most of it. Sawgrass is not really grass. It is a plant that has leaves edged with tiny sharp teeth that can easily cut through clothes—and skin!

Travel in the Everglades is difficult. You cannot walk through shallow water because the sawgrass will cut you. The water is too shallow for regular boats. So, we use an airboat. An airboat is a flat, open boat. Like an airplane, it has a big propeller to move it. The propeller is fixed on the rear of the boat. It makes a tremendous noise, but it does the job. The boat skims along the water’s surface. Although we can still get lost in an airboat, at least we are above the alligators(短吻鳄).

While hundreds of different kinds of animals live in the Everglades, the most famous is surely the alligator. Once endangered, alligators are now protected within Everglades National Park. Visitors are likely to see them both on land and in water.

For a long time, dangers have threatened the Everglades. Around 1900, some people felt this precious wetland should be drained (排干). They said it was just a big swamp and not good for anything. In the 1920s, there was a land boom in Florida. People wanted to build homes everywhere, including in the Everglades. They built canals, levees (防洪堤) , and other water systems that stopped the rivers flowing into the Everglades. Factories were built near rivers that flowed into the wetland. These factories dumped poisonous waste that damaged the Everglades ecosystem.

? People are now working to preserve the Everglades National Park for the future. Right now, one big problem is the paperbark tree. This tree is an invader from Australia.

Paperbark trees soak up a lot of water. In the early 1900s, people brought them to Florida because they thought they would help drain the Everglades. However, the invaders adapted too well. Paperbark trees have taken over hundreds of thousands of acres of the Everglades and killed other trees. Scientists are cutting down these invaders or spraying them with herbicides (除草剂) to kill them. ?

1.Which helps to explain why it is difficult to travel in Everglades?

2.Why do people use airboats instead of normal boats?

3.The following measures were taken to drain the Everglades except that people______. ?

4.The underlined word "invader" probably means something______. ?

The huge Florida wetland known as the Everglades is a slow-moving river 80 kilometres wide but only a few centimeters deep. People call the Everglades a “river of grass” because sawgrass covers most of it. Sawgrass is not really grass. It is a plant that has leaves edged with tiny sharp teeth that can easily cut through clothes—and skin!

Travel in the Everglades is difficult. You cannot walk through shallow water because the sawgrass will cut you. The water is too shallow for regular boats. So, we use an airboat. An airboat is a flat, open boat. Like an airplane, it has a big propeller to move it. The propeller is fixed on the rear of the boat. It makes a tremendous noise, but it does the job. The boat skims along the water’s surface. Although we can still get lost in an airboat, at least we are above the alligators(短吻鳄).

   While hundreds of different kinds of animals live in the Everglades, the most famous is surely the alligator. Once endangered, alligators are now protected within Everglades National Park. Visitors are likely to see them both on land and in water.

   For a long time, dangers have threatened the Everglades. Around 1900, some people felt this precious wetland should be drained (排干). They said it was just a big swamp and not good for anything. In the 1920s, there was a land boom in Florida. People wanted to build homes everywhere, including in the Everglades. They built canals, levees (防洪堤) , and other water systems that stopped the rivers flowing into the Everglades. Factories were built near rivers that flowed into the wetland. These factories dumped poisonous waste that damaged the Everglades ecosystem.

? People are now working to preserve the Everglades National Park for the future. Right now, one big problem is the paperbark tree. This tree is an invader from Australia.

    Paperbark trees soak up a lot of water. In the early 1900s, people brought them to Florida because they thought they would help drain the Everglades. However, the invaders adapted too well. Paperbark trees have taken over hundreds of thousands of acres of the Everglades and killed other trees. Scientists are cutting down these invaders or spraying them with herbicides (除草剂) to kill them. ?

Which helps to explain why it is difficult to travel in Everglades?

     A. Airboats may make a very big noise.

     B. You may get lost when passing through.

     C. Paperbark trees soak up too much water there.

     D. Many different kinds of animals are to be protected.

Why do people use airboats instead of normal boats?

     A. They have big propellers to move them faster than alligators.

     B. The propeller makes loud noise so as to scare alligators.

     C. Their flat bottom can skim along the water surface.

     D. They can watch alligators without hurting them. ?

The following measures were taken to drain the Everglades except that people______. ?

     A. built canals and levees to stop the rivers flowing into Everglades?

     B. built factories near rivers that flowed into the wetland?

     C. brought Paperbark to soak up water in Everglades?

     D. are cutting down these Paperbark trees?

The underlined word "invader" probably means something______. ?

     A. that moves in from another place     B. that enters and takes control?

     C. that has been brought in?                     D. that is in danger?

Losing a baby tooth can be fun for a kid. You can put it under your pillow and look forward to finding some money there in the morning. And then you can watch your new permanent(永恒的) tooth grow in its place.

But if a permanent tooth falls out, that’s a problem. There isn’t another one under the gum(齿龈)that can replace it. Unfortunately, this happens to some older people. And if permanent teeth fall out-or need to be pulled-an older person might need dentures.

Dentures, known as false teeth, are a set of replacement teeth for any teeth that are missing. There are partial dentures, which take the place of only a few teeth and prevent the others from changing position. If all the teeth are gone, the person would need complete dentures, which replace every tooth in the mouth.

Dentures can cause pains at first and take some time to get adjusted to. They also need special care. They should be brushed daily with a special denture brush and cleanser and soaked in denture solution when not in the mouth.

Dentures are important for older folks because, without teeth, it’s hard to smile, talk, and eat properly. But it can be a little weird if you see someone take out his or her dentures. It can also be strange to see someone, like a grandparent, without dentures in because he or she won’t have any teeth. Try not to make fun of the person because this could cause hurt feelings.

People usually lose their permanent teeth due to periodontal disease, or gum disease, which is caused by bacteria that attacks the gums. Diseased gums aren’t strong and healthy, so teeth can get loose and fall out. Older people often have many cavities(洞)that have been filled over the years, and these fillings can weaken over time, leading to more tooth decay(腐烂).

If one of your baby teeth falls out, he or she       .

A．should have a false tooth fixed in its place

B．have to put it under your pillow at once

C．will gain a permanent tooth in future

D．can exchange it for some money

A person wearing dentures      .

A．should brush them with a special denture brush every few days

B．will take a very long time to adjust himself or herself to them

C．will experience unpleasant feelings at the beginning of fixing them

D．should use denture solution to soak them in his or her mouth

Which of the following is NOT true according to the passage?

A．Partial dentures can prevent the remaining teeth from changing position.

B．Old people will find it hard to smile, talk, and eat properly without teeth.

C．A person’s teeth will possibly get loose if diseases strike his gums.

D．It is hard for a person to wear dentures if all his teeth have fallen out.

What does the underlined word “weird” mean in the fifth paragraph?

A．inconvenient           B．strange          C．uncomfortable       D．impolite