Grammar: Shut

Lambert left work at 7 pm every Friday night. He was always the last to leave. He walked out the building and turned around and shut the door. He locked it right away and then pulled out his ticket for the train and walked to the station. Sometimes he forgot to turn off one of the lights at the back of the office, but his boss turned a blind eye towards that since Lambert was otherwise very reliable. His boss could also shut the light off on Saturday, since he almost always came in to work on Saturday. He could always count on Lambert to shut down the factory on Friday night perfectly.