Well, I think, the main point that makes the difference between "Mending Wall" and “The Purple Cow” is actually demonstrated by the rhyme. Just read each poem one more time and feel that one of them is readed easily, words matched with each other like a song's lyrics so that you can smoothly go on reading whereas "Mending Wall" is made with structure of blank verse that emphasises every line and makes reader feel it deeply.
Answer:
1.They fight
2.He study hard all day
3.Somebody smoke in the room
4.She lie in the sun too long
5.They play football
6.She dream
A it is that he was too nice and his wife wanted him to be more wicked