英语翻译1 他肯定已经收到了我的信,因为我三天前就寄出了 must2 直到发生了事故,我才意识到遵守交通的重要性 not

1.He must have received my letter,because I sent them several days ago.
2.I haven't realized the importance of obeying the rule of traffic until the incident happened.
3.In the past few decades,he has been in possession of several apartments.
4.There is no doubt that the purpose of him to go to the art museum was to view these cherishable works.
5.Because he helped the company solve the problem of finance,he deserves the appreciation from the seniors.
都是我自己翻译的,应该没有大错,纯手打,