Brushing your teeth in Shanghai requires a bottle of water. This is because the tap water in Shanghai is not drinkable, so you can not brush your teeth with it unless you want a funny disease like "beaver fever" or really loud diarhhea. Of course, I detour this problem by using bottled water and putting it into a cup.
The process is fairly simple. Untwist the cap from a bottle of water. Pour it into a glass. Stick your toothbrush in (for wetting). Brush, as usual. Then use the water in the glass to rinse out your mouth and rinse off your toothbrush. Simple.
But what do you do when you're out of bottled water? Well, then you have to boil water in the kettle. And do the entire above process with boiling hot water. I really hate it, so I'm going to make sure I don't have to do it again. Tom usually brushes his teeth with warm water - at least he did in the states, but I like freezing ice cold water for the brushing of my teeth. Not boiling. Bleh.