Sentence:  With these aids , and a pair of skiis substituting for wheels on the Waco , Bob Fogg made the first landing on what <WSD>is</WSD> now part of the Barre-Montpelier Airport on November 21 , 1927 . 
Meaning of the word marked with <WSD> tags:  have the quality of being; (copula, used with an adjective or a predicate noun)