He would come if you were nice with him: il viendrait si tu étais sympa avec lui
In French too, we use the conditional mood.
Would you like some coffee? Voudriez-vous du café ?
After “if” conditional, French and English are similar:
If I had come (if I’d come)… Si j’étais venu.
We don’t use the conditional.
Willingness: She would not help me: elle ne voulait pas m’aider or elle ne m’aurait pas aidé!
For a repeated action: he would always watch tv before dinner: il regardait toujours la télé avant le diner.
Here, we use the Imparfait.
To express the future in the past:
“This morning Paul said he will be going shopping tomorrow“.
Ce matin, Paul a dit qu’il ira faire des courses demain.
“Last tuesday Paul said he would be going shopping the following day“.
Mardi dernier, Paul a dit qu’il irait faire des course le lendemain.
As in English we use the conditional to express the future in the past.
If I had gone to that party, I would have had a good time.
Si j’étais allé à cette fête, Je me serais bien amusé
Here we use to be conditional + past participle (s’amuser needs to be as an auxiliary verb)
If I had heard the weather report, I would have taken an umbrella.
Si j’avais entendu la météo, j’aurais pris un parapluie.
As you can see, we use the conditional of the auxiliary verb + the past participle of the following verb, like in English, just be careful with the second auxiliary in French, être.