Поставьте глаголы, стоящие в скобках, в соответственную форму в страдательном залоге. 1. the new song (to be sung) tomorrow. 2. all the exams (to be taken) already. 3. the story (to be written) yesterday by the famous writer. 4. this problem (to discussed) at the conference now. the test papers (to be written) by the students twice a year