as much as i can

Yes...all the time. I have a strange fear of showing emotion to people other than the select few I keep close to me.

tried but failed, they come easily and uncontrollable

Yeah I try to when it gets like that coz years back I was real messed up and I ain't afraid to say it but giving in stops you going forward.
However if someone you know and Love dies or is Ill or you know something like that it's a bit different.

Some times, but other times I let them all go. It is really healthy to have a good old fashioned bawling session occasionally.

when i am alone i don't bcoz tht's the time when u can let ur emotions flow otherwise i try to hold back them as much i can

Unfortunately, I have to say yes.When I was growing up my family lived a very straight forward,factual life. I didn't see this emotion so I didn't acknowledge this emotion.When I feel tears,I fight them back especially if there is someone close by that can see/hear me.I get embarrassed and upset with myself for crying.I also felt it was a sign of weakness.I wish I didn't feel this way,I work on it though.Now I'm able to shed a few tears over something emotional. The only thing ...No one can be around or the tears won't come.When I have cried,it felt good to release the emotions that are pent up.

When I have to.

Sometimes u cant control ur feelings, and sometimes u want to cry because its going to make u feel better.

Of course not, lachrymose effluvia erupt from my ocular orbs quite often.