I. Підкресліть в кожному реченні присудок та вкажіть його форму. Речення перекладіть.

1.He has for many years been in the forefront of research into important areas of O.R. (operations research) methodology.

2. Therefore, when the acceleration is sufficiently large, the lag will have increased.

3. By three o’clock the new pump had been working for two hours.

4. The steel plant had carried out its yearly plan by the first of November.

5. We have not noticed any change in the tested bar for two hours.