Task: Question Answering
Input (English): One of the buttons came off on my shirt, so I have to sew it back on. Sewing a button can be tricky, since you need a very steady hand. I get some thread and a sewing needle and get to work. I carefully put the button on my shirt, and start sewing. I tie a knot on the end of my thread, and put the needle through the underside of my shirt to where the button is. I guide the needle from under the shirt through one of the holes in the button, and then back through another hole. I do this many times, alternating between the four holes to make sure the button's on tight. There are a lot of ways you can sew a button, but I like to do it so the stitch looks like an X. Once I've done it enough times, I can tie off my thread and my button's as good as new! 
Question: When did they stop sewing the button?
Output (English): after sew tightly