一天,妈妈带我去小吃店吃面。我叫服务员给我一次性的筷子,妈妈说:“不要再用一次性的筷子了。”我不明白,一次性的不好吗?方便又卫生。妈妈问:“你知道一次性筷子是用什么材料做的吗?”我迫不及待地回答:“当然是用木材做的。”妈妈说:“是的。但是,一棵树,需 One day, my mother took me to the snack bar to eat noodles. I called the waiter to give me a one-time chopsticks, my mother said: “Do not use disposable chopsticks again.” I do not understand, one-time bad? Convenient and hygienic. Mom asked, “Do you know what disposable chopsticks are made of?” I can not wait to reply: “Of course it's made of wood.” Mom said, "Yes, but a tree needs