1.Wei suddenly saw a watch lying on the ground.
Suddenly a watch lying on the ground was seen by Wei.
2.Mr Black was ill, so Miss Green was taking his class instead.
Mr Black was ill, so Miss Green was taking the class instead of him.
3.He couldn't pass the maths exam.
He failed to pass the maths exam.
4.THe teacher told the girl not to worry.
The teacher told the girl to be at ease.
5.I'd love to attend your birthday party,but I'm very busy these days.
I want to attend your birthday party, bur I'm very busy these days.
6.I will tell him the news as soon as she arrives at the school.
I will tell him the news as soon as she gets to the school.
7.He is a public school student.
He isn't a private school student.
8.Chen worked harder than any other student in his class.
Chen worked hardest in his class.
9.He's studying hard in order to pass the exam.
He's studying hard on purpose to pass the exam.
10.Shanghai is the biggest city in our country.
No other city is bigger than Shanghai in our country.