在下坂本有何贵干秘技:as a scratching post

as a scratching post "as a scratching post"的意思是什么? as mad as a door as light as a feather AS*A=MAN such as a spreadsheet THERE WAS ONCE A POST OFFICE as mad as a door 是什么意思? writing increased as a problem as students AS +adj(原级)+AS,请问AS 的用法???a