둬왔으며

In a sentence

• 나는 항상 동생의 선택을 존중해 둬왔으며, 그의 결정을 지지해왔다.

  I have always respected my sibling's choices and supported his decisions.

  The term '둬왔으며' here conveys a continuing state of giving respect or regard over time.

• 그 회사는 다양한 혁신적인 솔루션 개발에 힘써 둬왔으며, 고객들에게 신뢰를 얻으려 노력해왔다.

  That company has been striving to develop various innovative solutions and has tried to earn the trust of customers.

  In this sentence, '둬왔으며' illustrates the sustained effort or focus in the action of striving over a duration.

• 나는 그 책을 연구 자료로 사용하려고 보관해 둬왔으며, 필요한 때마다 참조하고 있다.

  I have kept that book for use as research material and refer to it when needed.

  Here, '둬왔으며' expresses the continuous action of keeping something for a specific purpose or intention over time.