The waste gas and water (are)poured into the .( )里是is还是are?

问题描述:

The waste gas and water (are)poured into the .( )里是is还是are?

如果两个不可数名词合在一起,用and连接,表示一个整体,就用单数.如:Bread and butter is a nice breakfast.
如不表示整体,则用复述.Music and dance are both wonderful.