Of the following sentences, which one is correct?
I took Linguitics with Mr.Smith
I took Linguitics from Mr.Smith
I think they have two different meaning. "With" means he was a fellow student. "From" means he was the teacher.
In British English, '... with Mr Smith' could mean a teacher or a student; context would usually make the meaning clear. '... from Mr Smith' is unnatural.
There are different answers so I'm in doubt which the right answer is.
In any case, context will normally make the difference clear, even if you choose a preposition that sounds a little strange to your listener. If you are worried about this, change the structure: 'Mr Smith taught me French'; 'Charlie Smith was in my French class at college'.