Learn Portuguese (Portugal): A rapariga absorta deu por si a olhar fixamente para o ecrã. - The engrossed girl suddenly realized she was looking fixedly at the screen.

The structure dar por + reflexive pronoun (like si or mim) + a + infinitive is a specific expression used to describe the exact moment you snap out of a daze and catch yourself in the middle of an action. Here, deu por si means she caught herself, and a olhar provides the ongoing action she caught herself doing.

Could we use consigo instead of por si in this sentence?

Yes, you can absolutely say deu consigo a olhar instead. Both structures mean catching oneself doing something. When you use the verb dar with the preposition por, you use the prepositional pronoun si. If you use the preposition com instead, it merges with si to form the single word consigo.

Why does the adjective absorta come right after rapariga?

In Portuguese, adjectives describing a temporary state or condition typically follow the noun. Absorta means absorbed or engrossed. Placing it immediately after the noun emphasizes that this was her temporary state of mind at that specific moment, perfectly setting the scene for her sudden realization.

I have seen the word tela used for 'screen' before. Why is ecrã used here?