The intersection of the inner and outer surfaces of the cylinder is different from the intersection of the shape of the intersecting line and the outer surface of the two cylinders.
【简答题】Fill in the blanks with the proper forms of the verbs. 1) He (use) to be a teacher ten years ago. 2) I will tell her the good news as soon as she ( come) home. 3) When the bell rang, I (do...