▲两种表达都可以，均表示“整个……”“……一整天”，即：

正：all Monay, all Tuesday, all Wednesday, all Thursady, all Friday, all Saturday, all Sunday

正：all of Monay, all of Tuesday, all of Wednesday, all of Thursady, all of Friday, all of Saturday, all of Sunday

均表示：星期一、星期二、星期三、星期四、星期五、星期六、星期日一整天

▲相关例句：

It rained all Monday but stopped raining during the night. 星期一整天都在下雨，但夜里雨停了。（《牛津实用英语语法》）

I spent all of Saturday just puttering around, not really getting anything done. 我星期六整天都在闲逛，没有真正做任何事情。（《美国英语习语和短语动词词典》）

She was in the office all of Wednesday and so has a cast-iron alibi. 她星期三一整天都在办公室，所以有不在犯罪现场的铁证。（《牛津英语搭配词典》）