kept at retard

• v. 使迟延(阻碍)

kept at retard的用法和样例：

例句

1. I knew if I kept at it I should succeed.
   我知道如果我坚持下去就会成功。
2. The food should be kept at low temperature.
   这种食品应低温保存。
3. Mary kept at her homework until she finished.
   玛丽坚持把作业写完。
4. If you keep at your work, you will finish it soon.
   如果你坚持干下去，很快就会完成的。
5. Keep at it.There is only a little more.
   坚持下去，只剩一点儿了。
6. The laboratory is kept at a uniform temperature.
   实验室保持恒温。