mk cần câu trả lời chi tiết tại sao bn lại có câu trả lời như vậy ạ ! 11. The contracts signed by the company (have) been voided because some stipulations were not met. 12. Ten miles (be) . a very long distance for us to walk. 13. Each package that is not properly wrapped (have) . . to be returned to the sender. 14. The keys of the house (have) . been lost. 15. The plan as well as the proposals (be) . . to be presented in the coming Monday meeting. 16. The box of ribbons for the electric typewriter (have) . . been misplaced. 17. It is disconcerting to believe that every possible candidate (have) . . been rejected for one reason or another. 18. There (have) . been more excitement in this city about a sporting event. 19. To me, Mathematics (be) something very easy to master. 20. If nobody (have) . . bought that car from the dealer, then you should return and make another offer. mk cảm ơn mn nhiều ạ!