By seeing if they pay more attention to you or hangs around you alot
No there is not it is good to have friends but maybe someone likes you more than a friend and you just don't know it.
Well it depends on whether she likes him as more than a friend or not. I have been out with my best friends friend but that didnt end too well so I suggest that you talk to her about how she feels about him.
Ask her.
If he likes to spend more time with your friend rather then you that would be one way of telling.
how he lookes at you
YOU ASK THEM
if he talks more to you then he likes your friend because guys are shy so they do not talk to the girl they like. So if the guy talks more to your friend then he likes you.
Walk away.She will feel like she is losing you in some way and make it more obvious to you in some way. If your friend likes her more, again-walk away. Don't let a girl come between a good friendship. Let him have her. Also you can ask her if she likes your friend
If he likes you instead of your friend, he will pay more attention to you. He will be spending more time on you than your friend.
If a guy wants to spend more one-on-one time with you, he probably likes you as more than just a friend.
If he wants to spend more one-on-one time with you and enjoys your company, it may mean he likes you as more than a friend.
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