x1 [observer] senses/detects/notices stimulus x2 (object/nu) by means x3 under conditions x4.
x1 is sensitive to x2; also feels, spots, perceives, makes out, discerns/recognizes (but only implying reaction without necessarily any significant mental processing); note that the emphasis is on a property which stimulates x1 and is detected (sanji is passive about the sensing, and is not limited to sensory input, as well as presuming some kind of discernment/recognition, while not being concerned with the means of detection); x3 sense/sensory channel. See also pencu, sanji, viska, sumne, tirna, zgana, canci, simlu.