5KM/A/IS/WALK/THIS/TO/BEACH/THE.A. THIS IS A WALK TO THE BEACH 5KM...

21. 5km/a/is/walk/this/to/beach/the.

A. This is a walk to the beach 5km. B. A 5km walk to the beach is this.

C.To the beach is this 5km walk. D. This is a 5km walk to the beach.

Đọc đoạn văn sau rồi điền vào chổ trống từ thích hợp nhất bằng cách khoanh tròn A, B, C

hoặc D. KEEPING OUR TEETH HEALTHY

How can we keep our teeth healthy? First, we ought to visit our dentist twice a year.He can fill the

small holes in our teeth before they destroy the teeth. He can examine our teeth to(22)...that

they are growing in the right way.Unfortunately, many people wait until they have toothache

before they see a(23)...Secondly, we should brush our teeth with a(24)...and fluoride

toothpaste at least twice a day- one after breakfast and(25)...before we go to bed. We can

also use wooden toothpicks to clean between our teeth(26)...a meal. Thirdly, we should eat

food that is (27)...for our teeth and our body : milk, cheese, fish, brown bread, potatoes, red

rice, raw vegetables and fresh fruit. Chocolate, sweets, biscuits and cakes(28)...bad,

especially when we eat(29)...between meals. They are harmful(30)...they stick to our teeth

and cause decay.