⋯⋯，因而⋯⋯
Explanation
“⋯⋯，因而⋯⋯”是表示因果关系的复句结构，“因而”相当于“因此”、“所以”，用于引出前句所述原因所导致的结果。这个结构多用于书面语，比“所以”更正式。
"⋯⋯, yī'érn (therefore/consequently) ⋯⋯" is a compound sentence structure expressing cause and effect. "Yī'érn" means "therefore" or "consequently" and is used to introduce the result caused by the reason stated in the first clause. This structure is more formal and commonly used in written language than "所以" (suǒyǐ).
Examples
他生病了，因而没来上课。
He was sick, so he didn't come to class.
她按时完成了任务，因而受到公司的奖励。
She completed the task on time, so she received a reward from the company.
这次考试太难了，因而很多学生都没有通过。
This exam was too difficult, so many students didn't pass.