中间等级

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.

上周三，科学家们将喀拉喀托和唐库班珀拉胡的度由“正常”提高到“告”，三的中间等，因为这两近来定期喷出灰，并发出隆隆的声音。