阅读与表达。

     Eating in space is different from eating on Earth. The food that astronauts carry with them does not look

  like the food you eat.

     Some food is carried in closed bags. It is cooked and frozen (冷冻) before the astronauts get it. All the

  water is removed from the food. In the spaceship, the astronaut puts the water back. He "shoots" hot or

 cold water into the food bag with a special gun. He eats the food through a small hole in the bag. Other

 foods come in bite sizes. The astronaut puts a whole piece in his mouth at once. There can be no crumbs

 (碎屑). Crumbs would float (漂浮) around the spaceship and get in the way. Meat and cake often come

 in bite-size pieces.

     Astronauts cannot drink water from open cups. The water would float in drops in the air. The water is

  put in the special gun. The astronaut shoots the water into his mouth.

     Eating in space is not easy. Astronauts must learn to eat in their way.

1. What is the food carried in closed bags by astronauts like?

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2. How do the astronauts eat food in space?

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3. How do the astronauts drink water in space?

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4. Why can't the astronauts drink water from open cups?

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5. What is the main idea of the passage?

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