Вследующих предложениях замените действительный залог страдательным. 1)this mine produces very much coal. 2)he will mention this fact in his report. 3)rastrelli designed the winter oalace in st.petersburg. 4)they have solved the problem. 5)you may learn all the things in the next room. 6)we couldnt send off the letter yesterday.

1)Very much coal is produced by this mine.
2)This fact will be mentioned by him in his report.
3)The Winter Palace was designed by Rastrelli in St.Petersburg.
4)The problem has been solved by them.
5)All the things may be learnt by you in the next room.
6)The letter couldn`t be sent off by us yesterday.