notice是可数名词还是不可数名词?

　　例句：（可数）

　　There is a notice on the office gate saying "No Parking". 办公室门口上贴着一张"禁止停车"的告示。

　　We have put a notice of renting these flats in the newspaper. 我们已经在报上登了出租这几套房的启事。

　　例句：（不可数）

　　The hotel is closed until further notice. 宾馆现已停业,开业时间另行通知。

　　These rules can't be changed without notice. 这些规则不预先通知不可以随便更改。