Quelqu’un frappe à la porte; j’y vais.

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Breakdown of Quelqu’un frappe à la porte; j’y vais.

• aller: to go
• à: at
• la porte: the door

Questions & Answers about Quelqu’un frappe à la porte; j’y vais.

Is Quelqu’un one word? What’s the apostrophe doing there?

Yes—Quelqu’un is a single word meaning someone/somebody. It historically comes from quelque + un, but it is written together with an apostrophe: quelqu’un. It is invariable (no plural) and takes a singular verb.

Is Quelqu’un masculine? Do we ever say quelqu’une?

By default, quelqu’un is grammatically masculine. You can see quelqu’une (feminine) when you want to emphasize the person is female, but it’s much less common. The verb still stays in the third person singular either way.

Why is it frappe à la porte and not frappe la porte or frappe sur la porte?

• frapper à la porte = to knock at/on the door (idiomatic for knocking).
• frapper la porte = to hit/strike the door (not the usual way to say knock).
• frapper sur la porte = to bang/strike on the door (more physical/forceful). For a normal knock, use à.

Why à la and not au?

Because porte is feminine. à + la stays à la. You would use au only with masculine singular nouns (à + le → au).