A yawn response can be considered to occur within 5 min after perceiving someone else’s yawn (the trigger’s yawn) (Provine1986), with a peak in the first minute (Palagi et al.2014; Provine2005). However, in th
But they are only sure that when one person yawns, immediately everyone else nearby wants to yawn, too. 【1】The underlined word "contagious" in Paragraph 1 means___. A. helpful to our health B. passing from one person to another C. hard to understand D. getting into one trouble afte...