So I have come across this a few times. I am holding a straw to a persons lips and they drink and drink and drink and pretty soon they are waving their hands for me to stop. Stop what?! You don't have to keep sucking on the straw just because it is in your mouth. I think the universal sign of I'm done please remove the straw should be to stop sucking on it and open your mouth! I have had a few people have to catch their breath and make comments about me giving them too much! What? I don't get it.