6、Most of the ways to turn salt water into fresh water coste

6、Most of the ways to turn salt water into fresh water costed a lot of money.
改错:划线词是
Most of the ways, salt water, into ,costed
7、Other wastes ____into streams, such as acids from mines and facrories.
A have been dumped B was dumped C have dumped D has dumped
8、In photosynthesis plants __water and salts in the soil,a dn carbon dioxide in the air.
A combine B connect C construct D concern

大部分把咸水转化为淡水的方法都很费钱!