subjunctive clause

[kurtkei]

1.If I were you ,I would learn English well .

2.If you were here yesterday ,you whould meet him .

3.The meeting will be put off if it rains tomorrow .

4.If you followed the doctor's advice, you would be better now

is it right? thank for your response

[Tdol]

2- If you'd been here yesterday, youwould have met him.
4- If you had followed the doctor's advice, you would be better now.