Depuis, pendant, il y a, dans, en
CEFR B2 · part 1
edumaterial's parts within the level. The European framework does not subdivide them.
The past before the past: le plus-que-parfaitForming the plus-que-parfait with the imperfect of the auxiliary, and using it for what…Compound relatives: lequel, auquel, ce dontChoosing the relative when a preposition comes first, contracting with à and de, and…Negation beyond ne… pasChoosing the second half of the negation, placing it correctly with infinitives and the…Present participle, gérondif and verbal adjectiveTelling apart the three -ant forms: the gérondif with en, the present participle that…Stressed pronouns and pronoun orderUsing moi, toi, lui, eux after prepositions, in comparisons and for emphasis; and…Accents and the cedillaPlacing é, è, ê and ç correctly, and knowing that in French an accent changes the sound…The rule, in three lines
Depuis = since when, with the present if it is still going on. Pendant = how long it lasted, finished. Il y a = so long ago. Dans = in so much time, future. En = how long it takes to do it.
The usual slip. Using a past tense with depuis. French uses the present: «j'habite ici depuis trois ans», because he still lives there.
Why it catches you out. English uses the present perfect with for and since, so the tense is wrong from the start. And for covers both depuis and pendant, which are not the same thing at all.