Sentence:  The mean refractive error at six metres for the subjects was !-0.14D. and so the average total accommodation exerted was (0.14 + 2.51) 2.65D. for a dioptric distance of 3.0D. Thus, all of the observers <WSD>under-accommodated</WSD> for the near fixation distance when white light was used. 
Meaning of the word marked with <WSD> tags:  To adjust the focal point of the eye so that the image of the target falls short of the retina.