he waited until the volcano became quiet and he was able to return two days later.
问题描述：
he waited until the volcano became quiet and he was able to return two days later.
wait和became不是动词吗,一个句子,不是不能出现双谓语吗,这是怎么回事
答
确切地讲,这是个主从复合句
主句he waited
时间从句until the volcano became ...（until是引导状语从句的“从属连词”）
所以可以的,而且必须,要不就不成句子了.再说主句从句都该是完整的句子.
你的支持就是我的动力!