Sentence:  It was so cold and so wretched that a sort of desperate gaiety infected all of them , like people stormbound or shipwrecked or caught in some other freak of circumstance so that time stood still and minor anxieties fell away and the only important thing <WSD>was</WSD> to cling together and survive . 
Meaning of the word marked with <WSD> tags:  be identical to; be someone or something