1. Each generation young people usually get taller compared with the typical adult. A new style of buses ( should have been / must have been ) developed earlier considering this. But there has been no consideration for the difficulties young people have had. Now it is high time that we made a plan for young people. We ( may design / must design ) a new style of buses. 2. The waiter came to take the dessert, and left the check. Harshan picked up the check first, but Bob insisted that he ( had paid / pay ), and managed to convince Harshan. The waiter took Bob's credit card and returned soon with the check and credit card slip. 이거 답이랑 왜 그런 건지 알려줄 수 있을까?