In the 1960s the puzzle was partially solved by the theory of density waves, developed by Chia-Chiao Lin and Frank Shu, both then at the Massachusetts Institute of Technology.是什么意思_In the 1960s the puzzle was partially solved by the theory of density waves, developed by Chia-Chiao Lin and Frank Shu, both then at the Massachusetts Institute of Technology.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句