collaboration, joint action, combined effort, teamwork, partnership, coordination, liaison, association, synergy, synergism, give and take, compromise
The definition of time as something that passes and is centred in the now is contained implicitly in the use of the tenses ... Clocks do not measure the passage of time but translate temporal intervals into spatial structures.
It is
"The life of an immigrant is difficult.
Immigrants tend to live in one area."
I think.