Directions:
For each blank in the following passages there are four words or phrases
marked.
A,
B, C and D. Fill in each blank with the word or phrase that best fits the
context.
(A)
It
is very important to have healthy teeth. Good teeth help us to chew our food.
They also help us to look nice.
How
does a tooth go bad? The 51 begins in a little crack in the enamel (珐琅) covering of the tooth. This happens after germs and bits of food
have 52 there. Then the decay slowly spreads inside the tooth. In the
end, poison goes into the blood, and we may feel quite ill.
How
can we keep our teeth 53 ? First, we ought to visit our dentist twice a
year. He can fill the small hales in our teeth before they destroy the teeth.
He can 54 our teeth to check that they are growing in the right way, 55
, many people wait until they have toothache before they see a dentist.
Secondly, we should brush our teeth with a toothbrush and fluoride (氟化物) toothpaste at least 56 a
day-once after breakfast and once before we go to bed. We can also use wooden
toothpicks to 57 between our teeth after a meal. Thirdly, we should eat
food that is 58 to our teeth and our body, milk, cheese, fish, brown
bread, potatoes, re rice. raw vegetables and fresh fruit. Chocolate, sweets,
biscuits and cakes are bad, especially 59 we eat them between meals.
They are harmful because they 60 out teeth and cause decay.
51.
A. destruction B. decay C.
fault D. hurt
52.
A. stored B. collected
C. laid D. piled
53.
A. healthy B. complete
C. effective D. painless
54.
A. observe B. skim C.
watch D. examine
55.
A. Unexpectedly B. Certainly small C. Unfortunately D. Generally
56.
A. once B. twice C.
three times D. four times
57.
A. drill B. dig C.
clean D. explore
58.
A. delicious B. valuable C. beneficial D. meaningful
59.
A. what B. how C.
whether D. when
60.
A. stick to B. attach to
C. fix on D. keep to