Plz tell me why do we use "from" in this sentence I am suffering from fever.
Also tell me why do we use "at" in such sentence:-he is walking at 8 km/hr when "at" is used for position of rest.
1. It's just the preposition we use after "suffering"
2. The rules you learn for prepositions will always have exceptions; although you could say that his speedometer pointer is sitting at the 8 km/hr indicator.