Then she swam to the shore after spending the whole night in the water.这句话不解

题目

Then she swam to the shore after spending the whole night in the water.这句话不解
Then she swam to the shore after spending the whole night in the water.
意思是：她已经在水里呆了一晚上之后才游的
还是：她游了一晚上?
怎么看出来的呢

答案

她在海里游了整整一夜 才游到岸边.
有after在……之后