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更多“astronaut（）”相关的问题
A．shall be
B．be
C．are to be
D．must be
A.He was a teacher
B.He was an astronaut
C.He was a reporter
D.He was a policeman
He'll be an astronaut by the time he ______ thirty.
A．is
B．had been
C．will he
D．is going to be
Other foods come in bite size. The astronaut puts a whole piece in his mouth at once. There can be no crumbs. Crumbs would float around the spaceship and get in the way. Meat and cake often come in bite-sixed pieces. Astronauts can' t 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 this way.
Some space foods are carded in ______ .
A．water guns
B．lunch boxes
C．closed bags
D．food bags
Food for space has to be packed in special ways. Some of it goes into tubes that a man can squeeze into his mouth. Bite-sized cookies are packed in plastic.
There is a good reason for covering each bite. The plastic keeps pieces of food from travelling in the spaceship. On the earth very small pieces of food would simply fall to the floor. But gravity doesn' t pull them to the floor when they are out of the plastic in a spaceship. (78) They move here and there and can get into a man' s eyes or into the spaceship' s instruments. If any of the instruments is blocked, the astronauts may have trouble getting safely home.
As astronauts travel on longer space trips, he must take time to sleep. An astronaut can fit himself to his seat with a kind of seat belt. Or, if he wants to, he can sleep in a sleeping bag which is fixed in place under his seat. But be careful he must put his hands under the belt when he goes to sleep. This is because he is really afraid that he might touch one of controls that isn' t supposed to be touched until later.
Why would astronauts cover each bite of food in space？
A．Because small pieces of food would fall down to the floor.
B．Because weightless pieces of food might make trouble when they travel around.
C．Because they haven' t enough food for longer trips.
D．Because astronauts don' t want to waste food.
