CMR 

\(2< \dfrac{a+b}{a+b+C}+\dfrac{b+C}{b+c+d}+\dfrac{c+d}{c+d+a}+\dfrac{d+a}{d+a+b}< 3\)

Tìm số TN n≥1 sao cho tổng 

1!+2!+3!+...+n! là số chính phương

Cho a,b,c>0 vaf a+b+c=3 CMR \(\dfrac{a+1}{b^2+1}+\dfrac{b+1}{c^2+1}+\dfrac{c+1}{a^2+1}\text{≥a+b+C}\)

IV. Change into reported speech: Command, Order, suggestion, invitation, advice...

1. “ Stay in bed for a few days,” The doctor said to me. (told)

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2. “Don’t wait for me if I am late.” John said to us. (told)

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3. “Please don’t tell anybody what happened,” Ann said to me. ( asked)

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4. “ Can you open your bags, please?” The customs officer said to me, (asked)

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5. “You should take the job, Frank.”, Sandra said. ( advised)

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6. “ Would you like to come on a picnic with us?” Mike said to me. ( invite)

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7. “Don’t wear those boots in the house.” She said to her child. ( asked)

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8. Mr. Green said, “Please come to my dinner tomorrow. Bill” …………………………………………………………………………………………….

9. The policeman said, “Don’t touch anything here.”

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10. The father said, “ Keep your body warm, my son.”

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11. I said to them, “Please, don’t watch late night movies.”

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12. The life guard said, “ Don’t swim out so far, boys.

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13. He said to me, “Do this test again , please.”

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14. The teacher said to the students, “Don’t make noise in class.”

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