阅读下面材料，在空白处填入适当的内容或括号内单词的正确形式。
From an early age, Parker always said that he would be an astronaut. But no matter ____ much he studied, worked, and took tests, he never passed. Finally, he ____(grow) over the maximum(最高的) age for taking the test. He would never be able to realize his dream.
People ____(feel)sorry for his dream. Although he ____(tell) about having to give up his dream, Parker continued training and studying, as though he was going to sit the tests next month.
He carried this on as he got ____(old), and when he was a very old man he heard that they were doing some very important medical experiments. For those experiments they needed ____very old astronaut. Parker, who now walked with a stick, was the only old man in the whole world who was trained to fly in a rocket.
So Parker found ____(he) flying in space at last. The experiments were very ____ (succeed). The knowledge from the experiments helped doctors to cure one of the ____ (bad)sicknesses for old people, and Parker was celebrated as a hero. Photos of the astronaut with a walking stick and no ____(tooth) spread all over the world. It showed that persistent effort always brings reward, even though that reward may not be in the form we had first expected.
