Ba nguyên tử X,Y,Z có số hạt proton lần lượt là ba số lẻ liên tiếp và tổng số các hạt electron của nguyên tử là 39. Hãy cho biết số hiệu nguyên tử của ba nguyên tố? giup mik!!!!!

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Exercise 4: Put the verbs in brackets in the correct forms. 11. Those shirts need (iron) _______________, but you don’t need (iron ) _______________ them now. 12. That author doesn’t mind (criticize) _______________ by his friends. 13. Bill’s wife doesn’t let him (go) _______________ go to the party. 14. I don’t allow (smoke) _______________ in my drawing-room. I don’t allow my family (smoke) _______________ at all. 15. A lot of things need (do) _______________ to the house before we can move in. 16. Children enjoy (tell) _______________ ghost stories on Halloween night. 17. I am afraid of (take away) _______________ by the strong wind. 18. She regret (tell) _______________ Peter her secret. 19. Peter expected (introduce) _______________ to the Director. 20. The students in this class were made (learn) _______________ very hard. 21. I will let you _____________ (borrow) my car if you promise ____________ (take) care of it. 22. She can’t stand (watch) _______________ all day by her parents. 23. They refused (accept) _______________ the bribe. 24. You had better ________________ (see) your doctor ________________ (check) your health annually. 25. Mary regrets ________________ (tell) Tom the truth because he can’t keep it a secret. 26. We hope (invite) _______________ to discussions with the company. 27. She hates (look) _______________ at by the others. 28. It is no good (feel) _______________ sorry for yourself. 29. The plants need (water) _______________ daily. 30. The bank robbers made the cashier (show) _______________ them how (open) _______________ the safe.