Sentence:  Next year is the 80 th anniversary of the signing of the treaty between Korea and the United States and experts in Seoul are <WSD>trying</WSD> to find the correspondence between Frederick Frelinghuysen , who was secretary of state in 1883 and 1884 , and Gen. Lucius Foote , who was the first minister to Korea . 
Meaning of the word marked with <WSD> tags:  make an effort or attempt