Strawberries contain high levels of vitamin C, which helps make your teeth whiter. Take a few strawberries and crushed. Now use this mixture to gently scrub your teeth. If done daily for two weeks, dull yellow on your teeth will gradually disappear.
Another way is to mix 1 part of the meat with a strawberry half teaspoon baking powder, then rub the mixture onto your teeth and leave for a few minutes. Finally, rinse your mouth and brush your teeth with toothpaste to remove the clinging things.