Read Edit View history 元古代 Yuángǔdài Proterozoic Origin Definitions Defs Strokes Stroke Words Sentences Sents created sense approved 元古代 · Yuángǔdài · Proterozoic 2026/03/04 元古代 Yuángǔdài Proterozoic Proterozoic (geological era 2500-540m years ago) 元古代是地壳演化的重要阶段。 time word created sense Mar 4, 2026, 02:25 AM