英语GUESSING GAMEThere was once a manager.He was busy all day.

英语GUESSING GAME
There was once a manager.He was busy all day.But many people came to his office and talked to him for hours.At last the manager put a note on the door of his office.Now here is the note:
IM2B2CU
Do you know what it means?
翻译：
有一次一位经理.他整天忙.但是很多人来他的办公室并且对他交谈好几个小时.最后经理把笔记放在他的办公室的门上.现在这是笔记 ：
IM2B2CU
(我总是搞不懂是什么意思_