operation作為手術可數嗎

　　The system has been in operation for six months.

　　這個系統已經執行六個月了。

　　The operation could prolong his life by two or three years.

　　這次手術可使他多活兩三年。

　　His quality of life has improved dramatically since the operation.

　　手術後他的生活質量大大改善了。

　　The new rules come into operation from next week.

　　新規定從下週起實施。

　　Will I need to have an operation?

　　我需要動手術嗎？