（ ），wood will soon burst into a flame.
A.Heating
B.When heating
C.Being heated
D.When heated
參考答案:（ ），wood will soon burst into a flame.
A.Heating
B.When heating
C.Being heated
D.When heated
选D，这是一个省略从句主语的句子，记住：只有当主句和从句主语相同时才能省略啊。原句应该是When it is heated,wood will soon burst into a flame. 受热以后，木头会窜出火苗。（被动语态，所以用heated）
