II. Use a suitable prefix to complete the sentences (dis-; non-; un-; im-; il-; ir- 1. People should be more polite with (able) people. 2. I (agree) with your statement. 3. This airline is (responsible) because of the (regular) flights. 4. (Fortunately) I’ve missed the meeting last week. 5. (Stop) aggression causes the raise of (likes) . 6. It’s (possible) to (appear) without any traces. 7. It’s (moral) to humiliate (literate) people. 8. (honest) people don’t have friends.

1. unable;

2. disagree;

3. irresponsible, irregular;

4. unfortunately;

5. unstop/nonstop, unlike;

6. impossible, disappear;

7. immoral, illiterate;

8. dishonest.

1. Some helping in exchange of information is provided by scientific conferences.
2. He demonstrates some insisting on addressing this issue.
3. Being engaged in collecting material for a new article is my occupation now.
4. Arising of this error from the use of approximate methods occurs
often.
5. Aiming at obtaining accurate data on this issue - that is what the efforts of many scientists are focused on.
6. In this connection, other studies in this field are worth mentioning.
7. In this article, suggesting the usage of the same principle when considering more complex systems is done by the author.
8. Preventing a new series of experiments from being conducted  is caused by the lack of accurate data.
9. Trying to answer this question has been performed by scientists for a long time.
10.  The reason for some differing in providing more accurate data lies in this method.

1. By next summer the swimming pool will have been built in this street.
2. By three o'clock my work will have been finished already.
3. By the time you come back the flat will have been to tidied up
4. will the supper have been cooked by the time the children come from school?
5. By next year this house will have been reconstructed
6. I hope by winter this road will have been repaired
7. I think by tomorrow the guestion will have been settled.
8. By the time he comes all traces will have been hidden
9. You can't go to the library at eight tomorrow. By that time it will have been closed
10. They think that by next winter the reconstruction works will have been finished and they'll be able to let the tourists see the gallery.