Do you know how to keep fish at home?
The fish need room. They must not be crowded（拥挤）. Fish need oxygen(氧气). Fish get it from water in the tank. There must be enough water for all fish in the tank. So the size of the tank is important..
In the tank many people put small plants(植物). They give oxygen to the water. Plants help in other ways, too. Fish can nibble(轻咬)on the plants. They hide in the plants and sleep, lay eggs there.
Both the plants and fish need light. You can put near a window. It will get light there. But remember: a window may let cold air in. The cold can kill(杀死) your fish. Too hot water can kill your fish, too.
The fish need food and you should feed them every day. Giving them too much food is bad. It will make the water dirty. However, the fish should get just enough food. They should finish the food in 10 minutes. No extra(多余) is left. When this happens, the amount(数量)of food is right.
(   )16. A tank near the window may NOT be good for pet fish because________.
A. no air can get in through the window   B. pet fish will jump out of the window
C. plants in the tank will grow too big     D. cold air may make the water too cold
(   )17.________is very important to pet fish.
A.  Water    B.  Sunlight   C. The size of the tank      D. All the above
(   )18. Which of the following may cause（导致） pet fish to die?
A. Too little room for fish.             B. The plants in the tank.
C. The light through the window.        D. A lot of water in the tank.
(   )19. The word "this" in the last paragraph refers to(指的是)________.
A. giving pet fish too much food           B. giving pet fish too little food
C. giving pet fish the right amount of food    D. giving pet fish enough water
(   )20. This passage mainly talks about______________.
A.why fish must be put in a glass tank   
B. how people should keep their pet fish
C. what kind of plants is good for pet fish
D. how much food should we give to pet fish

完形填空
阅读下列短文，从文后各题所给的四个选项中选出一个最佳答案。
Do you know why different animals or pests(害虫) have their special colors? Colors in them seem to be mainly used to ___1___ themselves.
Some birds like eating locusts(蝗虫), but birds cannot ___2___catch them. Why? It is because locusts change their__3___ with the change of the colors of crops. When crops are green, locusts look ___4___. But as the harvest time comes, locusts change into the same brown color __5___ crops have. Some other pests whose colors are ___6__ plants are easily found and eaten by ___7___. So they have to hide themselves for lives and appear only __8____.
If you ___9___ animals’ life, you’ll find the main use of colors is to protect __10___. Bears, lions and other animals ___11___ quietly through forests. They cannot be easily seen by hunters ___12___ their colors are much like the trees.
Colors are useful not only on the land, but also in the __13___. A kind of fish can __14____ a kind of black liquid(液体) when they face danger. The liquid spreads over quickly, so they cannot be found by their enemies and can quickly swim away. That is ___15____ they can live safely though they are not strong at all. So colors are really useful to animals.

Li Ming likes walking. He goes for a walk after his father comes back from work. Li Ming likes water very much. He often throws his toys into the water. He plays with the water and sometimes he is wet all over(全身湿透). His mother says, “You are from fish, I think.”Li Ming is very glad. “Yes, I like fish very much because fish can swim.”
One Sunday morning, Li Ming goes to a park with his father. There are many trees and flowers in the park. There are a lot of people in the park. Some of them are sitting under the trees. Some of them are sitting at the tables and having tea or drinks. There is a big swimming pool in the middle of the park. Li Ming asks his father to take him to the pool.
“Why do you want to go there?” asks his father.
“I want to learn swimming,”answers Li Ming. “And you can teach me , I think.”
“You are too young. And I’m sorry I can’t swim.” says his father.
“You can’t swim? Wang Hai’s father swims very well. Why can’t you swim?”
“His father likes eating fish. So he swims very well.” Says his father.
“Oh, I see,”says Li Ming. “But you like eating chicken very much. Can you lay eggs(下蛋)？”asks Li Ming.
根据短文内容，选出最佳答案。
【小题1】Li Ming often walks with        .