4) поставьте глаголы-сказуемые в соответствующей видо-временной форме: 1. quite a large number of definitions (to give) to statistics as a science. 2. the war (to bring) major changes in the programme of statistical work and the methods of observation and processing. 3. all progressive knowledge in the modern world (to tend) to precision. 4. at present many countries (to declare) themselves republics, some of them (to become) independent and encourage the use of local languages. 5. they (to work) there for more than three hours when it (to happen). 6. nowadays some difficult economic problems (to be solved) on the basis of statistical data. 7. a theory (to be known) to be tested by practice.

1. Quite a large number of definitions (are given) to statistics as a science.
2. The war (has brought) major changes in the programme of statistical work and the methods of observation and processing.
3. All progressive knowledge in the modern world (is tending) to precision.
4. At present many countries (have declared) themselves republics, some of them (have become) independent and encourage the use of local languages.
5. They (had been working) there for more than three hours when it (happened).
6. Nowadays some difficult economic problems (are being solved) on the basis of statistical data.
7. A theory (is known) to be tested by practice.