After a preposition, the infinitive
CEFR B1 · part 2
edumaterial's parts within the level. The European framework does not subdivide them.
on, the French way to be impersonalUsing on where your language uses a passive, and building the être passive only when it…After si, never the futureBuilding all three conditional types, and never putting a future or conditional after si.Spoken French and written FrenchRecognising what is normal in speech but not in writing, and switching register without…celui, celle, ceux, cellesReplacing the noun without repeating it, and always following the pronoun with de, qui…en France, au Portugal, à ParisChoosing the preposition by the gender and number of the place, for going and for coming.le mien, le tien, le sienAnswering «whose is it?» without repeating the noun, with the article in front and…The rule, in three lines
After a preposition French uses the INFINITIVE: avant de partir, sans dire un mot. The one exception is en, which takes the gérondif.
The usual slip. Putting an -ing after every preposition, because that is what English does.
Why it catches you out. In English every preposition is followed by -ing: «before leaving», «without saying», «instead of going». French does the opposite, so you break the rule in every sentence of the paragraph.