The best way to find out is to ask her.
Or, if you want to find out without actually talking to her, ask her friends and try and find out if she likes you. If not, then it won't be embarrassing to ask her.
iam in love with this guy but i do not know if he likes me or some other girl
You let her down gently and try not to hurt her and this is a clue to see if the girl you like likes you You will know if she acts weird around you and avoids you more than anyone else.
When he has a penis.
If someone likes you they will spend time with you, laugh at your jokes, smile with you, talk to you, look at you when they could be doing something else. It doesn't matter who you are, you can always tell if someone likes you.
Just ask him. He will let you know with his mouth or his body language.
ask
both
If a girl breaks up with you it's either she no longer feels ready (depends on how long you've been going out) or she prefers someone else to you or she thinks you're cheating on her.
And let her\him know the real you not some fake image you might give off. And try to impress her as best as you can.
Let them know how you feel :)
if you know that then why dont you get someone else that really likes you that would never cheat on you
The same way everyone else know who they like.