Sentence:  Mr. Blatz had been at least sober enough to remember to telephone and he turned out to be the greatest boon that had come into Mr. Crombie 's life since he moved to Highfield , in spite of the fact that he did n't work very fast or very long <WSD>at</WSD> a time , and he did n't like to work at all unless Mr. Crombie hung around and talked to him . 
Meaning of the word marked with <WSD> tags:  simultaneously