1. altogether：altogether是副詞，意思包括
全部地，完全地（entirely)
例句：The noise has altogether stopped.
總***（including everything)
例句： I’d like to have nine oranges altogether.
總而言之（considering everything）
例句：Altogether, the progress is very great.
all together: 是副詞性詞組，意為“總***、壹起”
例句：I paid ?96 all together for the tickets.
例句：people were all together for the 2008 Beijing Olympic Games.
在做“總***”意思用時，altogether 和 all together可以互換使用。