Breakdown of Se ele se portar mal, vai ficar de castigo.
ele
he
de
of / from / by (means of transport) / wearing (attire)
ir
to go
mal
badly
Questions & Answers about Se ele se portar mal, vai ficar de castigo.
Why are there two words spelled se so close to each other in this sentence?
They are actually two completely different words! The capitalized Se is the conjunction meaning 'if'. The second se is a reflexive pronoun meaning 'himself', because the verb is portar-se (to behave). Literally, it reads as 'If he behaves himself...'.
Is portar in the infinitive here? It looks exactly like the dictionary form.
It is actually the Future Subjunctive tense, which you must use after Se when talking about a likely future condition. For regular verbs like portar, the Future Subjunctive forms happen to be spelled identically to the Infinitive!
Why does the reflexive pronoun se come before portar instead of attaching to the end?
In European Portuguese, pronouns normally attach to the end of the verb. However, certain 'magnetic' words pull the pronoun to the front. The word Se is one of these magnetic words, so it forces the pronoun before the verb, making it Se ele se portar instead of Se ele portar-se.