"If you rub your chopsticks too much they'll become sharp and you'll prick your mouth."
- "If you rub your chopsticks too much they'll become sharp and you'll prick your mouth."
"If you rub ~" 「〜をこすったら」
"your chopsticks" 「箸」・「あなたの箸」
"too much" 「余計に」
"they'll become sharp" 「トゲトゲでできて」
"you'll prick your mouth" 「口に刺さるよ」
If you rub the chopsticks together, it will make them even rougher and might end up poking your mouth.
"If you rub the chopsticks together, it will make them even rougher and might end up poking your mouth." という表現が使えます。
さらに、以下のように言うこともできます。
It's better to get new chopsticks instead of rubbing them. 「こするより、新しい箸に変えたほうがいいよ。」
オーストラリア 
アメリカ合衆国 
