1. He was reading a book at five o'clock yesterday. 2. Will you go for a walk with me? — I am sorry, I can't. I am doing my homework. I haven’t written the English exercise yet. 3. Where do you usually take books for reading? 4. What was he doing when you saw him yesterday? 5. I have never heard of her. 6. This little boy has never seen a crocodile. 7. What are you reading now? — I am reading Tom's book. 8. Autumn has come. It is November now. It is getting colder, the days are getting shorter. It often rains. Soon it will be very cold. 9. Our students have done all kinds of exercises and now they are sure that they know this rule well. They hope they will make no mistakes in the paper.
For years, astronomers, scientists of all kinds, and even average people have wondered if there is such thing as life on other planets. Many dedicate all of their time to researching extraterrestrial life. Some believe researching something we have no proof of is a waste of time. Modern day telescopes have detected Earth-sized planets orbiting nearby stars. An ancient Martian rock shows signs of life, and scientists wonder if Jupiter's moon Europa contains life in its oceans. The idea that there is even a tiny hint of life that we share the universe with, not just living beings, but capable, intelligent life much like our own, opens new doors for further extensive research. Spacecraft have explored all of the planets in our solar system except Pluto, and so far there are no signs of extraterrestrial life. Though no life has been found, there is no reason to give up a search for something out there we don't know about yet. Are certain scientists right in proposing that life originated on Mars, and could still exist today? It all remains up for debate. To further one's education regarding life in outer space, knowledge of life and evolution must first be obtained. J.B.S. Haldane, a Scottish biochemist, and A.P. Oparin, a Russian biochemist, researched the formation of earth and concluded that "soon after the Earth's formation, the necessary chemical elements were present for complex molecules to form molecules that are needed for life," (19-4). To assess the possibility that life exists now, or has at some point, on some other planet or moon, we have to know whether the conditions there are/were much like life as we know it on Earth. The first requirement for life is liquid water; without it, any kind of life, is impossible. But, how do we know what other life forms require to survive if we have never interacted with them?
1. He was reading a book at five o'clock yesterday. 2. Will you go for a walk with me? — I am sorry, I can't. I am doing my homework. I haven’t written the English exercise yet. 3. Where do you usually take books for reading? 4. What was he doing when you saw him yesterday? 5. I have never heard of her. 6. This little boy has never seen a crocodile. 7. What are you reading now? — I am reading Tom's book. 8. Autumn has come. It is November now. It is getting colder, the days are getting shorter. It often rains. Soon it will be very cold. 9. Our students have done all kinds of exercises and now they are sure that they know this rule well. They hope they will make no mistakes in the paper.