What's Tomorrow? Or Was It Yesterday?

If tomorrow is another day what was yesterday, what is yesterday?
Is tomorrow already yesterday, or is yesterday tomorrow?
Do we really know the exact time, or is the human only catching the past?
Do we only see what has already happened?
Are we living in the past, or are there people living in the future?
Time is an illusion not to be tampered with.
One mis-hap and someone might not exist tomorrow, or was it yesterday they disappeared?
Now the question is how do we find the difference between the future and the past?