______ have you been learning to play the violin?—Since I was rive years old.

选出下列划线字注音全部正确的一项（2分）

下列各句中，没有语病的一句是（ ）

This is the best way ______ I have thoughtof ______ the problem.

As _____ sports fan, I’m looking forward to watching ____ 31st Olympic Games in Rio, Brazil.