Do you know about space vegetables？Have you ever eaten them？
    Space vegetables are grown from seeds that have been taken to and brought back from outer space.When they are brought back to the earth，these seeds will grow into the vegetables that are bigger，healthier and more nutritious （有營養(yǎng)的） than normal vegetables.However，some people worry about eating space vegetables.They think that space vegetables might be bad for us and could give us cancer.In fact，there's no need to worry.Here are some facts that we should know about space vegetables.
    Space vegetables are grown from seeds that are carefully chosen.After seeds are brought back from space，they are tested to make sure that the vegetables will be safe to eat.There are no signs of radiation （輻射） after testing.
    Space vegetables are better for us than normal vegetables.For example，space tomatoes stay fresh for twenty days，one week longer than normal tomatoes.
    Unlike genetically modified foods （轉(zhuǎn)基因食物），space vegetables have not been genetically changed.This means that no new genes are put into the space vegetables，so we can eat them safely.

Space Vegetables
Introduction	Space vegetables are healthy and nutritious.We needn't be （1） worried worried
Some （2） facts facts about space vegetables	Steps taken to make sure the quality of space vegetables	?People （3） carefully carefully choose seeds to grow space vegetables. ?People （4） test test the vegetables to make sure they are safe to eat.
	The advantage of space vegetables	Space vegetables are better than normal vegetables.
Conclusion	We can eat space vegetables safely，（5） because because none of genes is changed.