Đặt  \(A=\frac{1}{2x3}+\frac{1}{3x4}+\frac{1}{4x5}+\frac{1}{5x6}+\frac{1}{6x7}+\frac{1}{7x8}+\frac{1}{8x9}\)

\(A=\frac{3-2}{2x3}+\frac{4-3}{3x4}+\frac{5-4}{4x5}+\frac{6-5}{5x6}+\frac{7-6}{6x7}+\frac{8-7}{7x8}+\frac{9-8}{8x9}\)

\(A=\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+\frac{1}{4}-\frac{1}{5}+\frac{1}{5}-\frac{1}{6}+\frac{1}{6}-\frac{1}{7}+\frac{1}{7}-\frac{1}{8}+\frac{1}{8}-\frac{1}{9}\)

\(A=\frac{1}{2}-\frac{1}{9}=\frac{9}{18}-\frac{2}{18}=\frac{7}{18}\)

1. My father (have)....has.....coffee for breakfast every day.

2.Hí sister (study)......studies.....in a shoe store this summer.

3.The students (look).....are looking.....up that new word now.

4.Marry (go).......goes......to shool every day.

5.They (do).....are doing........this exercise at the moment.

6. Ms Eden (read).........is reading...a newspaper now.

7. It (rain)......rains.......very much in the summer. It (rain).......is raining......now.

8. Bad students never (syudy).........study.....hard.

9. He generally (sing).....sings.......in English, but today he (sing).sings.........in Spanish.

10. We seldom (eat)......eat......before 6.30.

11. She sometime (buy).....buys.........vegetables at his market.

12. We always (do)..........do..........our exercises carefully.

13. Look! A man (run)...........is running....after the train. He (want)......wants......to catch it.

14. It (be).....is..........very cold now.

15. John (travel)........will travel.......tom England tomorrrow.

16. I (need).......need........some money for my textbooks.

17. Tom (like)........likes.....to go the museums.

18. Marry (love).......loves.....ice-cream.

please read the dialogue......................

A. aloud     B.loud      C. loudly   D loudily

1, his class has 53 students

how many students are there in his class?

2, Jim's flat is on the first floor

where is jim's flat?

3, we are in class 7B

which class are we in?

4, it's ten past twelve

what time is it?

5, my sister is in grade ten

which grade is your sister in?

6, she has lunch at 10.50

what time does she have lunch?

7, there is a boy in the park

how many boys are there in the park?

8, that is our teacher

who is that?

9, Mr John lives in the country

where does mr.john live?

10, our school is small

how is our school?

the most popular after school ___activities___ in our country    

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