When in Rome, do as the Romans do.
when in a new place, learn the rules and customs/traditions of the people there
Better late than never
better to do something late than not at all
The half is better than the whole
A moderate approach often yields the best results.
Every cloud has a silver lining.
All bad things have a good side.
Let the cat out of the bag
To tell a secret.
Don't judge a book by its cover
don't judge someone based on appearance alone
Sow the wind and reap the whirlwind
Every decision has consequences; a person's actions will come back to him.
Kill two birds with one stone
This idiom means, to accomplish two different things at the same time.
hate breeds hate
If you treat someone with anger or hatred, it will typically cause them to behave in a similar way to yourself or to others.
It never rains but it pours
problems always happen together