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1. There are many interesting articles in this magazine.
2. There are a lot of museums and theatres in our city.
3. Is there a telephone in this room?
4. There are two windows in this room.
5. There was no tea in the cup.
6. How many articles were there in this magazine? - There were several articles there.
7. How many students are there in the classroom? - There are twenty.
8. There will be a park close to our house.
9. Was there a school on this street?
10. There are several books on the table.
11. There is a school near our house. The school is situated close to our house.
12. There are a number of theatres in the city. Theatres are situated in the city centre.
13. There were flowers in the vase. The flowers were in the vase.
14. There are a lot of children in the theatre. The children are in the theatre now.
15. There are a number of ways to solve this problem. The ways of this problem solving are on page 5.

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.