Khi cọ sát hai vật bị nhiễm điện với nhau thì vật nào nhiễm điện dương vật nào nhiễm điện âm?

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/ Change into passive 1. What plays did Shakespeare write ?. -->.................................................................................................................... 2. They invited a lot of people to their party last night ………………………………………………………………. 3. Christopher discovered America in 1492 ……………………………………………………………………….. 4. A policeman took him to the police- station ……………………………………………………………………. 5. They have not used this machine for ages. …………………………………………………………………….. 6. They have paid doctor salot of money. ………………………………………………………………………. 7. Famous engineers have designed the aircraft. ………………………………………………………………… 8. Have several people just seen the accident? ………………………………………………………………….. 9. Who has written that novel ? ………………………………………………………………………………….. 10. Nobody has seen Tim since he left school in 1990. ………………………………………………………….. 11. Peter is writing a letter to his friend. ………………………………………………………………………….. 12. My friends are making some phone calls in the evening. ………………………………………………………. 13. Bad drivers are causing many accidents. ………………………………………………………………………. 14. Alex was preparing that report when I came to see him. …………………………………………………….. 15. Two houses were pulling the farmer’s wagon. …………………………………………………………………. 16. Waiters and waitresses were serving the customers. ……………………………………………………………… 17. The President was signing those papers. ………………………………………………………………………. 18. Was Mary helping her mother in the kitchen at that time ? …………………………………………………….. 19. What were you doing at that time yesterday ? ……………………………………………………………… 20. People play soccer all over the world. …………………………………………………………………………. 21. They have just told us about that. ………………………………………………………………………………. 22. My sister is writing that note in her notebook. …………………………………………………………………. 23. They keep those maps on the shelves for reference. …………………………………………………………… 24. They gave my little sister a ticket. …………………………………………………………………………….. 25. They have invited all the members to the party. ……………………………………………………………… 26. They have put up banners and flags in the square. ……………………………………………………………. 27. The headmaster was making the announcement. ……………………………………………………………… 28. They make Honda cars in Japan. ……………………………………………………………………………… 29. You must keep your dogs in the garden. ……………………………………………………………………….. 30. We will issue the library cards soon. …………………………………………………………………………