碰到脸熟的同事，你会主动打招呼吗？如果会，那么对方就在你的hello list--“打招呼列表”上。当然，这个列表也是不断变化的。如果这个人从来不主动和你打招呼，那么下次你的“打招呼列表”中也将不再有他。
Hello list refers to the list of people you have to or want to say "hello" to on a daily basis, especially relevant for students in university buildings, or coworkers in a workplace. Some people might decide to put you on their hello lists, even if they aren't on yours. Typically, reciprocity is expected.
“打招呼列表”指的是你平日里碰见时必须或想打招呼的人，那些经常穿梭于教学大楼的学生，或单位里的职员，都会有这样一张“打招呼列表”。某些人也许会把你放在他们的“打招呼列表”里，尽管他们并不在你的列表上（意思是他们会主动和你打招呼，而你不会）。不过，通常他们也期待你以后会主动和他们打招呼。
Example:
例句：
Dropping someone from your hello list to just a nod when you pass him or her might be considered a snub by the other person.
把某人从“打招呼列表”里移除，碰到时只是点点头，可能会被对方视作怠慢。
