Rewrite: You need to wear sunglasses to protect your eyes from the sun.You need to wear sunglasses so.................  

It is important to wear sunglasses in order to keep your eyes safe from the sun.

Wearing sunglasses is necessary to shield your eyes from the sun.

You need to wear sunglasses to prevent your eyes from being harmed by the sun.

You need to wear sunglasses so that your eyes are protected from the sun.