n.太陽(yáng)的黑點(diǎn)；黑子
We observe three sunspot groups on the disc. 在日面上觀測(cè)到三個(gè)黑子群。
This is an intriguing theory that droughts tie in with the sunspot. 這是一個(gè)關(guān)于干旱與太陽(yáng)黑子活動(dòng)周期有關(guān)的令人感到有趣的理論。
