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.

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