already是什么时态的标志?

　　例句：

　　We've already said our goodbyes.

　　我们已经道别了。

　　The car was already on the move.

　　汽车已经开动了。

　　She's backpedalled twice already.

　　她已经两次改变主意了。

　　Eight o'clock had already chimed.

　　已敲过八点钟了。