This study explores the learning process of 32 Chinese senior high school English as a foreign language teachers via three demonstration lessons. It was demonstrated via a data analysis of oral reports and interviews that the cognitive activity of “question,” which was considered a significant contributor to collaborative discussion, was seldom involved in the participating teachers’ learning process, and that the absence of this cognitive activity reduced their learning to individual study of the observed practical skills. The study further reveals (...) four factors that prevented the participating teachers from collaboratively constructing language teaching knowledge based on what was observed: These were their perceived purpose of the modeled lessons, their manner of making meaning, their understanding of observer–observed relationship, and their perception of professional learning. The analysis presented provides important insights for teacher educators to better facilitate in-service teachers of foreign languages learning through observation. (shrink)