Sentence:  Not only is Mr. Frelinghuysen a member of the House Foreign Affairs Committee , but he is the grandson of the man who was instrumental in <WSD>opening</WSD> relations between the United States and Korea , Frederick T. Frelinghuysen , secretary of state in the administration of Chester A. Arthur . 
Meaning of the word marked with <WSD> tags:  start to operate or function or cause to start operating or functioning