Предмет: Математика, автор: соник3

как решить это уровнение

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Автор ответа: katyscha00
2
Я так поняла: 40- 13х-7=21
-13х=21-40+7
-13х=-12
х=13/12 
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1. Choose the correct variant:

a) My hair is/are clean.

b) My family is/are happy.

c) Some people is/are coming today.

d) The scissors is/are sharp.


2. Make the plural of the nouns:

a) A boy –

b) A knife –

c) A fox –

d) A foot –

e) A lily -


3. Insert MUCH or MANY:

a) ______ people want to see this film.

b) He doesn’t drink _______ coffee.

c) How _______ sheets of paper do you need?


4. Fill in the article “THE” if needed:

a) Last year we visited _____Canada and _____ USA.

b) We went to ______Spain for our holidays and swam in ______ Mediterranean Sea.

c) _____Nile is the longest river in _______Africa.


5. Make the sentences negative.

a) I arrived home late last night.

b) He will eat his lunch at 2 p.m.

c) I’m reading a new story.

d) The bus comes at 7 o’clock every morning.


6. Make the sentences interrogative.

a) He is doing his homework.

b) We will go to the Black Sea next year.

c) You like ice-cream.

d) Father bought a red car two days ago.


7. Make up sentences

a) Are / wardrobes / the hall / there / in / two /?

b) a lamp / there / Is / room / your / in / ?

c) pears / there / ten / in the / are / bag /


8. Use the Present Simple Tense.

a) John (like) watching horror films..

b) We (walk) in the park every evening

c) Children often (visit) their grandmother

d) Tim (go) to work at 6 a.m.


9. Use the Past Simple Tense.

a) I (have) to do my project.

b) Willy (can not) speak German.

c) Mike (watch) a film yesterday.


10. Use the Future Simple Tense.

a) Jane (come) to me tomorrow.

b) I (go) to the theatre next week.

c) Irene (start) to keep her fit in a week.


11. Use the Present Perfect Tense.

a) Mother (already cook) dinner.

b) Students (pass) the test.

c) My cousin (live) in Belfast since 2001.


12. Present Perfect vs Past Simple.

a) I (learn) English since junior school.

b) My mom (be born) in 1959.

c) He (tell) you about it twice!


13. Past Perfect vs Past Simple.

a) I (come back) home, but the rain ( already stop).

b) I (wash) dishes before my mother (return) home.

c) He (forget) that he (already pay) the bill.


14. Conditionals.

a) Mary gave me the book if she (have) it.

b) You will improve your English skills if you (practice) more.

c) Mother (cook) a cake if father hadn’t forgotten to buy eggs.


15. Reported speech.

a) Mary said, “I’m so tired!”

b) Jerry said. “We bought a car yesterday”.

c) Jim said, “Mark has already done his homework”.

d) Mom said, “I am cleaning the house”.

e) Chris said, “I will help you tomorrow”.


16. Passive voice.

a) Mother cooked a cake.

b) Children draw pictures.

c) Father will buy a boat.


17. Read the text, is the sentences TRUE or FALSE?

The giraffe. The giraffe is the tallest animal. His head is about five meters above the ground. It has its good and bad sides. The giraffe can eat leaves from high trees because he has a long neck and a strong tongue. But it’s difficult for the giraffe to eat the grass. When the giraffe drinks water, lions and leopards often hide in the tall grass ready to catch him. It is very bad for the giraffe, because he can’t raise his head quickly and run away. The giraffe can live for months without water. He gets most of the water from what he eats. Also, because his heads is so far from the ground, a giraffe can see danger and can quickly walk away or run away. 1) The giraffe is the strongest animal. a) true b) false c) not stated 2) He has a long neck. a) true b) false c) not stated 3) The giraffe eats only grass. a) true b) false c) not stated 4) The giraffe can run fast. a) true b) false c) not stated 5) He can’t raise his head fast. a) true b) false c) not stated 6) The giraffe can’t live without water for a long time. a) true b) false c) not stated 7) He can see danger because he has a long neck. a) true b) false c) not stated


18. Choose the right word.

1. She is the daughter of my mother. She is my… a) aunt c) grandmother b) sister d) cousin 2. He is the father of my father. He is my… a) grandfather c) uncle b) grandson d) cousin 3. He is the father of my brother. He is my… a) uncle c) father b) son d) grandfather

4. He is the son of my uncle. He is my… a) cousin c) grandfather b) father d) brother 5. She is the sister of my mother. She is my… a) grandmother c) aunt b) daughter d) cousin 6. He is the son of my brother. He is my… a) cousin c) uncle b) nephew d) father