Learn French: Soudain, elle est tombée dans les escaliers.

In French, most verbs form the passé composé (past tense) using avoir (to have). But a special group of verbs that show motion or a change of state use être (to be) instead. Because tomber (to fall) is a verb of motion, we say elle est tombée (literally 'she is fallen') rather than using a.

Why is there an extra -e at the end of tombée?

When you form the past tense with être, the past participle (the main action word, like tombé) has to match the subject in gender and number. Since the subject is elle (she), which is feminine, we add an -e to make it tombée.

The English translation says she fell 'down' the stairs, but doesn't dans mean 'in'?

Exactly! In English, we focus on the direction and say we fall 'down' the stairs. French focuses on the location, so you fall 'in' the stairs (dans les escaliers). It is best to memorize tomber dans les escaliers as a set phrase for falling down the stairs.

Can I use a singular word for stairs, like l'escalier?

Yes, you can! Both l'escalier (the staircase) and les escaliers (the stairs) are commonly used in French to mean exactly the same thing. In this sentence, the plural is used, just like we often say 'the stairs' in English.