Time in relation to now

Now means at this moment. Then means at another moment (usually in the past) .

Example:

I was born in Berlin. Then we moved to Schwerin. Now I live in Rostock.

Other expressions:

It is 10 o’clock now .
I got up four hours ago , at 6 o’clock.
An hour ago it was 9 o’clock.

last year / last week / last Saturday
next year / next week / next summer

It is July now .
Last month it was June.
Next month it will be August

When we talk about time in general, we talk about the past , the present and the  future.

In the past people didn’t have television.
People will travel to Mars in the future .