Learn Portuguese (Portugal): Ele decide estudar inglês.

decidir (to decide) is a regular -ir verb. To conjugate it for ele (he), ela (she), or você (you formal) in the present tense, you drop the -ir ending and add -e.

Why is estudar left in its basic form instead of being conjugated?

Just like in English ('decides to study'), when you have two verbs back-to-back describing a single action, only the first verb (decide) changes to match the subject. The second verb (estudar) stays in its dictionary form, called the infinitive.

Why isn't inglês capitalized like the word 'English'?

In Portuguese, the names of languages, days of the week, and nationalities are written in lowercase. You will only capitalize inglês if it is the very first word of a sentence.

Is decide pronounced exactly like the English word?

No, the pronunciation is quite different! The emphasis is on the middle syllable (ci), and the final -e is not silent. In European Portuguese, an -e at the end of a word makes a very short, muffled sound, almost like a quick 'uh'.