Quelle est la différence entre "It has been raining since yesterday." et "It rains since yesterday." ???
- "It has been raining since yesterday."
It started raining yesterday and has not stopped since. (Most likely there have been a few short interruptions, but we are not thinking of them.)
- "It rains since yesterday."
Ever since yesterday, there have been some instances of rainfall. But it was no continuous rainfall. (Perhaps we are talking about a tropic or subtropic climate where it is normal to rain every day at certain hours. Until the day before yesterday, for some reason this did not happen. But yesterday it happened, and today it happened as well.)
PS: As BenYoung84 pointed out, normally one wouldn't even say "It rains since yesterday" because in the situation I described above that actually becomes "It has rained since yesterday".
Je ne suis pas d'accord avec johaquila. Je pense qu'on ne dit jamais "It rains since yesterday" en anglais. On n'utilise pas le temps present avec un marque du passe.
Plutot on peut dire "It has rained since yesterday". Ceci est la phrase qu'elle a la signification du dernier paragraphe de johaquila.