To make a word plural in Tagalog, use mga before it.
Mga anak mo ba sila?
Are they your kids?
Mga gamit mo ba ito?
Is this your stuff? (“Are these your things?”)
It is not always necessary to put mga before a word to make it plural. This is especially the case when the number is understood from the context.
Maghugas ka ng kamay.
Wash your hands.
Kumakain ka ba ng saging?
Do you eat bananas?
Maraming tao doon.
There are a lot of people there.