a piece - of paper什麼介詞

用介詞on，例如：

1、He wrote his name down on a piece of paper for me.他把他的名字寫在一張紙上交給我。

2、He ticked off my name on a piece of paper.他在一張紙上我的名字旁打了鈎。

3、The other day， I put down his number on a piece of paper， which I can't find now.前幾天，我把他的號碼寫在一張紙上，但現在找不到了。