Every person has two sets of teeth.The first set of twenty begins to grow when you are over six months old.The second set of thirty-two grows from the age of six until you are about twenty-one years old.
To help your teeth grow strong,you must drink plenty of milk and eat greens.
You should brush your teeth after each meal.Then few bits of food will be left on or between them to cause decay（腐爛.) Make sure that you turn the brush and go up and down as well as brushing side ways.Use dental floss to make sure all food is cleaned up from in between each tooth.If you cannot brush your teeth after eating,look after them with water,or eat an apple or a carrot.
How to __________ our teeth?
Number of the first set of teeth is _________.
The second set of teeth usually grow for _______ .
Milk and greens can make our teeth __________.
__________ left in our mouths may cause decay.
After meals we should __________our teeth.
We should visit a __________ twice a year.
If there are big holes in our teeth,we will have to __________ them taken out.
People usually have to __________much money using false teeth.
We should __________ all our second set of teeth as long as possible.
Try to visit a dentist(牙醫(yī)) every six months.If there is a hole in a tooth,he or she will fill it.If you do not have it filled,then the hole will grow larger.When a hole grows too big,the tooth may have to be taken out.It is better to keep all your second set of teeth for as long as possible.Filling a gap where a tooth has come out with a kind of bridge and using a false tooth costs a lot of money.