Time of action can be moment in time or period in / of time when an action takes place.
Time of action: words describing time for future actions
Tomorrow, the day after tomorrow, tonight, in two seconds / minutes / days, next +noun etc.
next + noun
Combinations:
Next time / Tuesday / weekend / week / month / year / century
in + noun
Combinations:
In a(n) second / minute / year / hour; in 2 years
Time of action: words describing time for past actions
yesterday, the day before yesterday, two seconds / minutes / days ago etc.
last + noun
Last Tuesday / weekend / week / month / year / century
noun + ago
a second / minute / year ago; an hour ago; 2 years ago
Time of action: words describing time for present actions
Today, now, at this moment, at the moment, this morning (if it’s still morning at the time of speaking), this year
this + noun
This Tuesday / weekend / week / month / year / century
Time for future and past actions
today, this month
At + time
At 1-12 o’clock, 1:45 etc.
On + weekday
On Sunday, Monday – Saturday
After / Before + noun , verb+ing
After lunch, before doing my lessons
Interestingly, some present tenses can express future actions. So, signal words describing actions in the future will also be in use here. I will give you just a quick example:
What time do you leave tomorrow? (scheduled time)
More on present simple future actions
Common signal words we use for future, present, and past tenses
today, this month / year / week
I will do it today
They did it today
I am doing it today
More on introduction to tenses:
More on Introduction to Tenses: