If he seems nice but acts rude sometimes, he may be the kind of guy who enjoys manipulating a girl’s emotions.
When you are confused as to why he acts nice one day and then rude the next, it keeps you worried and guessing about whether he likes you.
Sometimes, guys do this so as to exert control over the emotions of a girl.
This tends to put them in a position where they can play as many head games with the girl as they would like, thereby boosting their ego.
Some guys will behave this way, even with girls that they may like.
It may work to your advantage to start trying to have conversations with him that aren’t just work-related.
Doing this will give you a better idea about whether he is truly willing to open up to you and also learn more about you.
If you try doing this and he is still not making conversation with you or asking questions about you, then you may have true cause to believe that he isn’t interested in you.
If there is a language barrier, you should keep your conversations with him as uncomplicated as possible.
In other words, use common words and speak as clearly as possible.