He took pride himself on winning the competition.

took 是动词 take 的过去式，表示"采取、获得"等含义。 pride 是名词，意思是"自豪、骄傲"。 take pride in 是一个固定短语，表示"以...为荣、对...感到自豪"，这里用介词 on 替代了常见的 in，是较少见的用法。