5.3 课堂作业
Ⅰ.单词拼写
1．Water will turn into s________ when heated to 100℃.
答案：steam
2．Events in early childhood help to f________ our personalities in later life.
答案：form
3．I looked up at the clouds f________ in the sky.
答案：floating
4．To do the experiment, you need two ________ (天平) and some other materials that react with oxygen.
答案：balances
5．People are not allowed to use matches or any open ________ (火焰) in the forest.
答案：flame
6．Some substances don't ________ (溶解) in water whether they are heated or not.
答案：dissolve
