I can't do Math. 6 + 7 is too much for me. I can't sit still in my seat. I can't keep my hair neat.
I can read and I read very well...but, I can't answer questions about what I read.
I can throw and kick a ball with vigor and accuracy, but I can't usually beat the boys even though I try really hard.
I can spell and I never even have to study, but I can't seem to win the spelling contests in class.
I have enough energy to play from sun-up to sun-down, but not always someone to play with.
I can sing, but there isn't an appropriate venue for singing since I am only 6.
Hmmm...
I can get Bill out of bed in the morning. I can make him smile at me. I can change his diaper and I can feed him...
And there is no "but" in that sentence.