A transitional period is one in which things are changing from one state to another.
a transitional period following more than a decade of civil war.
十多年的内战结束之后的一个过渡时期。
We are still in the transitional stage between the old and new methods.
我们仍处在新旧方法的过渡阶段。
Transitional is used to describe something that happens or exists during a transitional period.
The main rebel groups have agreed to join in a meeting to set up a transitional government.
主要的叛乱团体已同意参加会议来讨论建立一个过渡政府。