管式空气预热器什么部位磨损最严重？原因是什么？如何防止？
Most people have no idea of the hard work and worry that gointothe collecting of those fascinating birds and animals that they pay to see in the zoo.One of the questions that is always asked of me is 1 I became an animal collector in the first 2.The answer is that I have always been interested in animals and zoos.According to my parents, the first word I was able to say with any 3 was not the conventional “mamma” or “daddy”,4 the word “zoo”, which I would 5 over and over again with a shrill 6 until someone, ingroupsto 7 me up, would take me to the zoo.When I 8 a little older, we lived in Greece and I had a great 9 of pets, ranging from owls to seahorses, and I spent all my spare time 10 the countryside in search of fresh specimens to 11 to my collection of pets.12 on I went for a year to the City Zoo, as a student 13 , to get experience of the large animals, such as lions, bears, bison and ostriches,14 were not easy to keep at home.When I left, I 15 had enough money of my own to be able to 16 my first trip and I have been going 17 ever since then.Though a collector's job is not an easy one and is full of 18 ,it is certainly a job which will appeal 19 all those who love animals and 20.
请在2处填上正确答案（） ["region","field","place","case"]
对异物吸入的小儿应（） ["嘱小儿蹦跳，将异物咳出","刺激咽喉部，使异物咳出","观察，必要时送往医院","拍背，帮助孩子咳出异物","立即送往医院"]
市场预测方法的选择？
球阀的代号为（）。
微创新的概念？
