Health is something we tend to (11) _______ when we have it. When our body is doing well, we are hardly aware of it. But illness can come, even (12) _______ we are young. In fact, childhood has been a very susceptible time. Many diseases attack children in particular, and people know very little how to cure them once they struck. The result was that many children died. About a century ago,(13) _________, scientists found out about germs, and then everything changed. The cause of many diseases ...

Health is something we tend to (11) _______ when we have it. When our body is doing well, we are hardly aware of it. But illness can come, even (12) _______ we are young. In fact, childhood has been a very susceptible time. Many diseases attack children in particular, and people know very little how to cure them once they struck. The result was that many children died. About a century ago,(13) _________, scientists found out about germs, and then everything changed. The cause of many diseases was found, and cures were developed. As this medical discovery spread, the world became____ (14) _____ safer for children. The result is that whereas a hundred years ago, the average man lived for 35 years, nowadays, in many areas of the world, people can expect to live for 75 years. And what do we expect by the year 2020? Undoubtedly, medical science will continue to (15) ________. Some people will be able to avoid medical problems that are unavoidable today.