Hello,

I have a site contains a lot of retail products, the site is available in multiple UI languages, but referring the same product (e.g. English & French in following example).

What URL format is suitable for me?

e.g.

1.

http://www.example.com/en/category1/product1
http://www.example.com/fr/category1/product1

2.

http://www.example.com/category1/product1?hl=en
http://www.example.com/category1/product1?hl=fr

3.

[en.example.com...]
[fr.example.com...]


Any idea?