Our future house will be on the ocean. It will be suronded by tall trees and blue sea. But only have salt water in the ocean. We needs fresh water for (1) drinking and for growing food on farms.
Ocean water is too salty (3) to drink. It is also too salty for watering plants. We must have the (4) ways to make fresh water from salty water. We should be (5) careful not to waste water.
1. a, drink b, to drink c, drinking d, to drinking
2. a, on b, at c, in d, into
3. a, drink b, to drink c, drinking d, for drink
4. a, things b, suggestions c, ways d, ideas
5. a, careful b, careless c, carefully d, carelessly