I. Open the brackets using the Present Perfect Tense, the Present Perfect Continuous Tense and the Past Perfect Continuous Tense.
1. It has been snowing
because all the cars out of doors are snowed in. - предложение само по себе неправильное...
2. Has she already finished
her laboratory work on chemistry? - Not yet, though she has been working
on it for more than 4 hours.
3. Boris is a 3d year student of the Institute of Priority Technologies of our University. He has been going
TO University for more than 2 years.
4. It was last Monday of October. Some experimenters had been working out
a new device since the first Monday of April.
5. Where is Peter? -Oh, don't disturb him . He has been reading
a very interesting book on the theory of criminal law for about 2 hours.
6. Since 9 a.m. the forensic experts have been examining
carefully a pistol left on the scene of murder. And now it's 4 pm.
7. Toxicologists have just found
some liquids in the flat of the victim of the murder.
8. Has he already finished
his diploma work ? - Not, yet, though he has been working
on it for 4 months.
9. It was some days ago. The scientsits had been analyzing
the problem for about a fortnight.
10. Mary is a 2nd year student of the Institute of Mathematics of our University. She has been going
to University for about 1,5 years.
11. I think that it has been raining
because it is damp and cool in the street.
12. It's 6 pm. What are they doing, I wonder? - oh, they have been discussing
one of the most difficult points in the modern criminalistics: the problem of identifying a criminal by his (her) voice since 2 pm.
13. Since 10 am they have been comparing
scratches left on bullets. And now its 5 p.m.
14. Toxicologists have already found
some illegal drugs inside the case of a suspect. Не забудьте нажать на кнопочки за нашу бескорыстную помощь! Вы реально поможете форуму.