Formerly believed to be the entrance to Hades, it is now a small lake in the crater of an extinct volcano west of Naples.   It is said that the mephitic vapors exhaled from the lake could kill birds flying over it. 

[解說]

1.      “Formerly believed to be the entrance to Hades”：以前被認為是地獄的入口。

2.      “it is now a small lake in the crater of an extinct volcano west of Naples”：現在它是一個小湖泊，在 Naples 西方一個熄火山的火山口。 “crater”：火山口。 “extinct volcano”：熄火山、死火山，不再 “erupt” (爆發) 的火山。

3.      “It is said that the mephitic vapors exhaled from the lake could kill birds flying over it”：據說，從湖泊散發出來的臭氣能殺死飛過它的鳥。 “mephitic”：惡臭的、有毒的。 “vapor”：蒸氣、霧氣。 “exhale”：呼出、散發，相對於 “inhale” (吸入)。 

[複習填充]

Formerly believed to be the entrance     Hades, it is now a small lake in the c       of an ex        volcano west of Naples.   It is said that the m         vapors ex         from the lake could kill birds flying over it.