- For Teachers
-I propose you check in a good learner's dictionary.
-I propose you(r) checking in a good learner's dictionary.
-I propose you to check in a good learner's dictionary.
I am aware that the first sentence is OK, but I am not sure the rest. Could you please tell me the second and third are OK or not?
Even the first is not very natural, in my opinion. I'd use 'suggest', not 'propose'.
It's wrong. You can use either 'if' or 'whether'.