Грамматики
17. Underline the correct variant.
1) The tigress was still looking for her cubs a week after they had been
disappeared / had disappeared.
2) This chess championship of the "giants" is being / is watched very closely.
3) You are being / have been warned!
4) Is the seat taken? / Has the seat been taken?
5) The system will be / will have been fully tested by tomorrow morning.
6) A new power plant has been /is being built causing concern of the
environmentalists.
7) The book was not published until every small detail had been / taas checked.
8) The police found that the wax seal on the jeweller's box was / had been broken,
9) The Olympic stadium will be have been constructed using modern technologies.
10) This human error could be / have been avoided.
11) The car was / had been invented right before the XX century.
12) This book was has been written in English.
19. Use the verbs in brackets in either Active Voice or Passive Voice. Black holes are some of the strangest things in space. A black hole 1) (to suck) in anything that gets by. Nothing escapes from a black hole. Not even light. Everything 2) (to pull) together. The reason is gravity. Gravity is a force that pulls one thing to another. Gravity is the force that 3) (to hold) you down on Earth. When you jump up, you 4) (to draw) back by gravity. The Moon 5) ＿ (to make) to orbit Earth by gravity. The more matter 6) (to pack) in a star, planet, moon, or other object, the stronger is its gravity. Gravity makes an object with more matter 7) (to pull) an object with less matter toward it. The Sun's gravity pulls on itself our Earth. The Sun 8) ＿ (to orbit) by Earth. The matter that makes up an iron ball 9) (to compress) much tighter than the matter that makes up a bag of feathers. A lot of matter 10) (to go) into a black hole. Astronomers and physicists think black holes 11) (to bear) from dying stars. Under the force of gravitation the star 12) (to make) denser and denser to turn into a black hole.