Unit 11. belong to 2. in search of 3.search for =look for 4. be used to do sth. 5. be used to doing sth. 6. in return7. serve as 8. be at war9. less than 10. great wonders of the world11. remain a mystery 12.become part of 13. take apart 14. tell the truth 15. pretend to do sth 16. think highly ofthink little of 17.agree with sb.18.(could/might /must /should)+ have done19. be worth doing 20. be designed for Unit 21. take part in/join in 2. find out 3. every four years 4two sets of 5. allow sb. to do sth. 6compete in compete for compete with/against7.be admitted to be admitted as 8reach the standard9.play an important role/part in 10. admit doing sth. be admitted to .11. run against 12.hear of 13make sure +that 14. take turns 15 one after another 16stand for 17. pick up/18make a bargain with 19.in charge (of) 20.in the charge of 21.free of charge 22.be charged with sth. 23.ask sb. for help Unit 3 1. begin as2. artificial intelligence3.technological revolution 4.solve a problem5. share with sb. 6. as a result 7. as a result of 8. with the help of9. after all 10. go by11. watch over12. once a year 13. in a way14. make up/15.in the way by the way on ones way to 16. as well as17. from on 18.deal with 19. have in common 20.according to 21. compare withCompare to 22. be filled with23. encourage sb to do sth 24.provide sb with sth= provide sth for sb Unit 41. die out/2.result in result from3. pay attention to sth /doing sth .4. in peace 5. hunt for 6.have an effect on / upon 7. be in danger of 8. turn around 9.protect from10.come into being 11. in relief 12. burst into laughter =burst out laughing 13. without mercy 14. according to 15. for sure 16. long to do sth Unit 51.dream of/about (doing) sth 2.at a concert 3.to be honest 4.be honest with sb. 5.form the habit of in the form of 6. earn extra money7. play jokes on8. be based on.9. break up10. sort out11.be confident of/ about / in 12. go wrong 13. above all 14. in addition 15. pay sb. in cash 16. attach importance to 17. rely on 18. be/get familiar with be/get familiar to