Time Markers
Recently
Long time ago
Sometime soon
Sometime in the future
Occasionally 
Frequently 
Long time 

Examples
I just saw the show. (Recently)
We met a long time ago. (Long time ago)
We have been working for a long time. (Long time)
They will do it again soon. (Soon next)
Maybe I will see you sometime in the future. (Sometime in future)
We exercise often. (Frequently)
I eat out once a while. (Occasionally)
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