dark galactic nebula的用法和樣例：
例句
- Galactic nebulas are masses of diffuse material within our galaxy.
銀河星云是我們星系中的一團團彌散物。 - Some celestial bodies similar to galactic nebulas but without any luminosity sometimes reveal their presence as dark patches obscuring the light of stars beyond them.
某些與銀河星云相似但不發(fā)光的天體，有時(shí)看來(lái)象塊黑色補丁，遮住了周?chē)男枪狻?/li>
