根据句子中的提示填空。

Can you i________(to form a picture in your mind of what sth．might be like)a blue horse with a yellow tail?

根据句子中的提示填空。

How long is the ________(旅行)to the coast?

根据句子中的提示填空。

Many cities are becoming more and more ________(拥挤的)．

根据句子中的提示填空。

The dog waited ________(希望)beside the table for some food．

根据句子中的提示填空。

Both Earth and Mars are p________．

根据课文回答问题。

Is the journey to Mars comfortable at present?

________________

根据课文回答问题。

Students will be very relaxed when they study on Mars, won't they?

________________

根据课文回答问题。

Who will do most of our work on Mars?

________________

根据课文回答问题。

How can we prevent humans on Mars from floating into space?

________________

根据课文回答问题。

Why can we easily jump high and float away into space on Mars?

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