—Do you know how to cook a cake?
—No,I don’t know how to do it.But do you know how to solve the difficult math problems?
—Yes,I know.I often use my calculator on my phone,it really helps me!
—Do you know how to cook a cake?
—No,I don’t know how to do it.But do you know how to solve the difficult math problems?
—Yes,I know.I often use my calculator on my phone,it really helps me!