story: Larry was trying to finish his book report before school. He wasn't done writing when the bus drove up. On the bus he continued working and didn't talk to his friends. With some difficulty he was even writing while walking up to the door. He put down the last period just as he entered the classroom.
 selected sentence: He put down the last period just as he entered the classroom.
Larry tries to finish his book report >Causes/Enables> Larry puts down the last period