1. => His exercises haven't been finished by brother. 

2. They are interested in joining the green City progam. I'm delighted.

=> I’m delighted that they are interested in joining the green City program.

3. I was very delighted that i passed the final exams.
=> I was very delighted to pass the final exams.
4. We find it difficult to understand this question.
-> This question is too difficult for us to understand.
7, I went to the colege . I wanted to see Professor Taylor.
-> I went to the college in order to see Professor Taylor.
8 ,she wore warm clothes , She didn't want to get cold .
-> She wore warm clothes in order not to get cold .
10, They must be warned of the danger.
11, It should be sent to us immediately.
12, The meeting won’t be held tonight