Dưới đây là các câu đã được sửa lại: 3/ Due to his slowness, we won't entrust him with such an important task. 4/ As I'll have to work this Sunday, I won't be able to join your picnic. 5/ He works overtime to earn more money as he needs to pay off his father's debt. 6/ City life is not enjoyable due to the high cost of everything. 7/ Everything on earth thrives because the sun always shines. 8/ Without a typewriter, I can't type it myself. 9/ I'll buy a new hat to give to you. 10/ If you ask the teacher, he will explain the lesson to you. 11/ Since Mary hasn't seen the sight, she can't tell you about it.