单词	of a cheerful countenance
释义	英華☞a cheerful countenance
随便看	hydrogen evolution reaction hydrogen evolution reaction (her) hydrogen excess pressure hydrogen exchange hydrogen explosion hydrogen exponent hydrogen filled cloud hydrogen filled cloud chamber hydrogen-filled cloud chamber hydrogen film hydrogen flame detector hydrogen flame ionization hydrogen flame ionization detector hydrogen flame temperature detector hydrogen flocculus hydrogen fluoride hydrogen fluoride alkylation process hydrogen-free dlc hydrogen fuel hydrogen fuel cell hydrogen fuel cell/battery hybrid vehicle hydrogen (fusion) hydrogen (fusion) reaction hydrogen (fusion)--reaction hydrogen fusion reaction