常見例句用作名詞 (n.)The tropical year is a phenomenon of the precession of the equinoxes in astronomy.太陽年是天文學(xué)里的歲差現(xiàn)象。A tropical year is a measurement of time from one winter solstice to the next.回歸年是指從一年冬至到下一年冬至的時(shí)間段。 返回 solar year