1,Viết lại câu
a, it is his duty to change the date of the meeting
=>he is supposed to change the date of the meeting
b, somebody repaired his car yesterday
=>he had his car repaired yesterday
c, he failed the exam because of his laziness
=> because he was lazy, he failed the exam
d, it was such a boring film that we left before the end
=>the film was so boring that we left before the end