Learn French: Je lisais quand soudain, la porte claque et je sursaute. - I was reading when suddenly, the door slams and I jump.

This is the présent de narration (historical present), which is the focus of this lesson. It is used in storytelling to make sudden or dramatic past events feel more vivid, as if they are happening right now. The imperfect (je lisais) sets the continuous background scene, and the present tense highlights the sudden interruption.

What tense would normally be used here instead of the historical present?

Without the narrative present, a sudden interrupting action introduced by quand soudain would typically use the passé composé in everyday speech (or the passé simple in written literature). You would normally say: Je lisais quand soudain, la porte a claqué et j'ai sursauté.

Is quand soudain a fixed expression?

Yes, quand soudain (when suddenly) is a classic phrase used to hook the listener and mark a sharp pivot in a story. You could also just use soudain or tout à coup at the start of a new sentence, but attaching it with quand beautifully emphasizes the interruption of the background action.

Besides a door slamming, how else is the verb claquer used?

Claquer is a versatile verb for sharp, popping noises. You can claquer des doigts (snap your fingers) or claquer des dents (chatter your teeth). In everyday spoken French, it is also frequently used as an adjective to mean exhausted, as in je suis claqué(e).