根据短文内容和首字母的提示，把所缺单词填写在短文后面的横线上。

     In the (1) m______ world, advertising is everywhere! Some people think that ads are great. Others

(2) h______ ads, saying that they make our cities and countryside look ugly. Many ads are (3) a______

specifically at teenagers, and some young people see more than 100 advertisements a day. It's true that

some ads can be very useful! For instance, they can help you to compare two different products so that

you can buy the (4)o______ you really need. They can also help you (5)s______ money. When prices are

listed, you can go to the store with the (6)l______ price.

如图所示的叶片泵传动轴加工工艺过程如下：工序Ⅰ，粗车外圆至

；工序Ⅱ，精车外圆至

；工序Ⅲ，铣键槽深度至尺寸

；工序Ⅳ，磨外圆至

。要求：磨后保证键槽深度

，试求：铣键槽时的槽深尺寸

。