last year是什么時態的標志詞

　　This year's results are virtually the same as last year's.

　　今年的結果幾乎和去年的一樣。

　　Company profits were 5% lower than last year.

　　公司的利潤比去年降低了5%。

　　The hospital closed at the end of last year.

　　這所醫院去年年底關閉。

　　The new wing was built onto the hospital last year.

　　醫院的新翼樓是去年增建的。

　　Sales are well up on last year.

　　銷量比去年大幅增加。