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
山和唐库班珀拉胡
山的警
度由“正常”提高到“警告”,
级警
的中间等级,因为这
山近来定期喷出
山灰,并发出隆隆的声音。