根据要求改写句子She bagan to write back.She received the letter.（合并成一句）
问题描述：
根据要求改写句子
She bagan to write back.She received the letter.（合并成一句）
答
She bagan to write back after She received the letter.
答
She bagan to write back after she received the letter./
After she received the letter, she bagan to write back .
答
She bagan to write back after she received the letter.
答
She began to write back after receiving the letter