Questions & Answers about To jest mój chłopak, a tam stoi jego dziewczyna.
In this kind of sentence, Polish normally uses the fixed pattern To jest + [noun] to introduce or identify someone/something:
- To jest mój chłopak. – This/That is my boyfriend.
- To jest mój brat. – This/That is my brother.
- To jest mój dom. – This/That is my house.
You could say On jest moim chłopakiem (He is my boyfriend), but that has a slightly different structure and feel. It’s more like a generic statement about him rather than a pointing/introduction phrase.
Ten jest is possible but rare alone; you’d normally need a noun with it, e.g. Ten chłopak jest mój (That boy is mine). For “This is my boyfriend”, the natural everyday pattern is To jest mój chłopak (or the shorter To mój chłopak, see below).