Questions & Answers about Mój brat studiuje tylko angielski.
Why does the verb studiuje have a -uj- in the middle?
The dictionary form of this verb is studiować (to study). In Polish, verbs ending in -ować change that ending to -uj- before adding the present tense endings. Since mój brat is "he" (third-person singular), we add the ending -e to the stem, giving us studiuje.
Can I use studiuje to say my brother studies in high school?
No, studiować is only used for studying at a university or college level. If your brother is in high school, or if he is just learning a language on his own, you would use the verb uczyć się (to learn/study) instead.
Why is it angielski here instead of angielskiego?
It depends on the verb! The verb studiować takes the Accusative case for its direct object. For inanimate masculine nouns like angielski, the Accusative looks exactly the same as the basic dictionary form. If you used the verb uczyć się (to learn), you would need the Genitive case: uczy się angielskiego.
Why is it mój and not moja or moje?