1) It is well known that radioactive isotopes can be used very effectively in medicine for the diagnosis and treatment of many diseases. 2) The simplest way of understanding what the cathode-ray tube does and how it does it is to follow out the various stages of its development. 3) It seemed to us that the engine was out of order. 4) It is silver that is the best conducting material. 5) I know only one solution of this problem. 6) One should keep in mind that when water is heated in a vessel, the liquid on the bottom of the vessel is hotter than on the top. 7) The simplest kind of lever is one in which the arms are of equal length. 8) They say that the report will be followed by a discussion. 9) That the device stopped working surprised everybody. 10) The result of this experiment is much better than that of the previous one. 11) Energy is defined as the ability to do work and it occurs in many forms. 12) As the water is in a state of rest there will be no flow of energy. 13) We shall carry out this research, for it seems to be very interesting. 14) He has been working at that design for 2 weeks. 15) I have brought some articles for you to translate. 16) But for friction, part of the energy developed by mechanical devices would not be lost in the form of useless heat. 17) For some minutes we could see nothing but black smoke rising from the ground. 18) There is no flow of electrons since the electric circuit is broken. 19) Since the release of the potential energy of the atomic nucleus we have entered the atomic age, we are living and working in now. 20) The vertical theory first put forward by Zhukovsky in 1912 has been used throughout the world since. 21) The higher up we go the smaller and lighter are the grains of dust in the air. 22) Many experiments made after helped us to come to an important conclusion. 23) When he had put on his spectacles, he saw that the handwriting on the envelope was that of his old friend. 24) I am that doctor Manette of whom you speak so nicely. 25) That the task was more difficult than we had thought before was clear to everyone. 26) One can go without food for some time, but one cannot live long without water. 27) The more he thought about it the more ridiculous it became. 28) Don't make him work so hard, you should keep in mind he is but a child. 29) She did not say anything more for a while. 30) I think that it is the only thing that would help you. 31) But for the ohms, amperes, volts and watts the electric measurements would be impossible.
