I was thinking today of how I would describe things in Japanese. One of these things was 'He's just a boy!', which I more or less worked out to be 「かれがしょうねんですしかよ！」which I THINK is correct, but still feels sorta 'off' to me. Something about the final noun using the particle 「しか」 AFTER stating the polite form of it.
Can't really put my finger on it, just feels like something's incorrect about it, thus I thought to ask.