Present perfect continuousform the negative and the interrogative.1. he has been working for hours.2. they have been studying since five o'clock.3. she has been learning english for two years.4. maria has been playing the guitar all day.5. i have been looking for my keys all day.6. his grandparents have been living in this house for forty years.7. helen has been washing the car since two o'clock.8. the baby has been sleeping all morning...9. we have been working here for many years.10. it has been snowing for two hours ​

1. One type of extinct creatures are dinosaurs. 2. The study of these extinct individuals is carried out by paleontologists. 3. Dinosaurs - one of the largest ever existed on Earth creatures. 4. Despite the fact that in drawings and movies dinosaurs are depicted in a variety of colors, scientists do not know what color the skin of a dinosaur had. 5. The length of the largest dinosaur reached 35 meters. 6. Dinosaurs died out at the end of the Cretaceous - early Tertiary period. 7. Extinction of the dinosaur is still considered one of the most interesting unsolved mysteries on the planet. 8. The smallest adult dinosaur representative was the size of a chicken.

1) If he had passed his exams, he might have gone to university.
2) If he had realized what was happening, he would have run away.
3) If I had heard what she  said, I would have been very angry.
4) If you had locked the door properly, they wouldn't have get in
5) If you had followed the instructions, It wouln't have happened.
6) If she had found out, she would have been furious.
7) If we hadn't  looked a room, we would have had nowhere to stay.
8) If we had been going any faster, someone could have been killed.
9) If he hadn't been so tired, he wouldn't  have gone home at lunchtime.