小测验：选择正确的单词

1. The dyke was built to retain the f1ood waters.
   那条堤坝是为拦洪修建的。
2. She retains a dear memory of her school days.
   她对学生时代保持清晰的记忆。
3. It has good heat-retaining properties.
   它有很好的保温性能。
4. He finds it difficult to retain information.
   他发现很难记事。
5. These roses retain their scent.
   这些玫瑰花仍有余香.

　1个形容词解释