核能是____ (选填“可再生”或“不可再生”)能源．氢能源具有广、热值高、无污染等优点．氢气的热值为14．3×107J／kg，完全燃烧0．5 kg的氢气可放出____ J的热量；若一罐氢气用去了一半，则剩余氢气的热值____ (大于／等于／小于)14．3×107J／kg．
— Helen, would you like to go to the park with me?
— .
运用经济生活知识说明政府采取以上措施对推动技术创新的意义。
We go to school from Monday to Friday. We have four classes in the____and three in the afternoon. We have____things to do after class. On Monday and____afternoon we have P.E. On Wednesday morning some of us have a singing class. On____morning some have a drawing class. On Friday____we practice speaking English.
