Two parts to my answer: 1. The grammar is not correct "inner relations" is plural, so you need "are" not "is". Or you need to change "relations" to the singular "relation". 2. Is it natural? No, not really. I think that you could improve things a bit by changing"inner relations" to "relationship", and maybe the second sentence to "William shook some pears and thus he became known as William Shakespeare." ... but still it's quite an unnatural thing to say because "Shakespeare" isn't pronounced as "Shakes-pear"...we say "Shakes-spear" , so the whole thing would work better if the first sentence was about the relationship between William and spears.

Relationship William shook pears I think some people are missing the joke!

The sentence is not grammatically correct, and its meaning is unclear. There is no inherent relationship between William and pears, and shaking pears would not result in becoming William Shakespeare. If you could provide more context or clarify your question, I would be happy to assist you further.

Yeah, I agree with the others. To the the pun right, he should shake SPEARS.