dùng kí hiệu ∀ và E ngược để viết các mệnh đề sau a) Có một số nguyên không chia hết cho chính nó. b) Mọi số thực cộng với 0 đều bằng chình nó c) Có một số hữu tỷ nhỏ hơn nghịch đảo của nó d) Mọi số tự nhiên đều lớn hơn số đối của nó

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10. I’m worried about the _________________ of the children. (safe) 11. Fire ________________ the house in the twinkling of an eyes . (destroy) 12 Keep those medicines out of _______________ of the children . (reach) 13. Nobody likes him because he behaves _________________ . (bad) 14. My mother bought a new gas ___________________ yesterday . (cook) 15. My sister is a good _________________________ . (cooking) 16. Tom isn’t a _________ student. He didn’t do very ________ in his exam. (good) 17. My Tam is a ___________ singer. She sings very _____________ . (well) 18. Studying ________________ help you to become a good cook . (cook) 19. You should learn to use electricity __________________ . (safe) 20. Electricity can cause serious ___________________ to users . (injure) 21. Make sure that everybody works ____________________ (safe) 22. Every ______________ in my neighborhood has at least one TV set. (house) 23. This river is very __________________for swimmers. (danger) 24. The _______________ of atom bomb is very terrible. (destroy) 25. Hard work always brings _____________________ . (succeed) 26. Those clothes are ___________________ for cold weather . (suit) 27. You can’t make a comparison between beef and oranges. They are completely _____________________ . (differ) 28. We should obey the ____________________ regulation of the hospital . (safe) 29. The __________________ victims were sent to the hospital yesterday . (injure) 30. You have to keep all ________________________ objects out of children's reach . (danger) 31. A kitchen is not a ___________________ place to play . (suitability) 32. Don't put the knife into an _________________________ socket . (electricity) 33. It is safe to keep medicine in ___________________________ cupboards . (lock) 34. Mary bought a new _____________________ yesterday . (cook) 35. Most ____________________ in the USA now own at least one car . (house) 36. I feel very ______________________ to be a part of a team . (pride) 37. The sky began to _______________________ in the East . (light) 38. My mother bought a new _______________________ machine . (wash) 39. We are listening to Helen's ______________________ of the wedding. (describe) 40. Mrs. Brown sells _________________________ goods . (electricity) 41. Smoking is a _________________________ to health . (danger) 42. Fire _______________________ the house in the twinkling of an eye . (destroy) 43. Nobody likes him because he behaves ______________________ . (bad) 44. My bought a new gas ________________________ yesterday . (cook)