Scientists on Wednesday raised the alert level for Anak Krakatoa and Tangkuban Prahu -- which regularly spew gas and rumble -- from "normal" to "warning," the middle of three alert levels.
上,
学家们将喀拉喀托火山
唐库班珀拉胡火山的警
“正常”提高到“警告”,
级警
的中间等级,因为这两座火山近来定期喷出火山灰,并发出隆隆的声音。