以：第三人称单数形式、过去分词、过去式、现在分词：为顺序

takes a trip，taken a trip, took a trip, taking a trip

sees a film, seen a film, saw a film, seeing a film

watches TV, watched TV, watched TV, watching TV

cleans the room, cleaned the room, cleaned the room, cleaning the room,

washes the clothes, washed the clothes, washed the clothes, washing the clothes

plays football, played football, played football, playing  football。