阅读理解
Tom and his father, Mr. Smith, always go out for a walk after supper every day. After that, he does his homework and watches TV for half an hour. Then he goes to bed. Now Tom and his father are taking a walk along the road. It begins to rain. Tom wants to run for home. But his father says very slowly, “Don't run. Isn't it raining in front of you?”
、
是两条不相交的直线，
、
是两个相交平面，则使“直线