【教学片段一】创设情境,引入“相交”与“不相交”师:我手中有两枝铅笔,请同学们想一想,如果我把手松开,这两枝铅笔掉在地上后会形成哪些图形?请同学们先独立思考,再用小棒摆一摆。 [Fragment of a teaching] to create the situation, the introduction of “intersect ” and “do not intersect ” Teacher: I have two pencils in my hand, please think about it, if I release my hand, these two pencils fell to the ground After the formation of what graphics? Please students think independently, and then put a small swing.