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Hi everyone,
I'm working on a website that has a quite extensive subfolder structure for product and multilingual purposes.
domain.com/en
domain.com/it
domain.com/fr
domain.com/en/category
domain.com/it/category
domain.com/fr/category
domain.com/en/category/product
domain.com/it/category/product
domain.com/fr/category/product
domain.com/en/category/product/region
domain.com/it/category/product/region
domain.com/fr/category/product/region
and so on... We will soon be launching a completely different service, which would make the subfolder structure become even more complex. As John Mueller recently stated that Subdomains and Subfolders are treated the same by Google, I am now considering building that new service under subdomains for product reason, and for the sake of clarity. 1- Would my subdomains inherit the authority of my main domain? 
2- Do I have to keep the language folders with the subdomain structure?
e.g.:
new-service.domain.com/en
nouveau-service.domain.com/fr
nuovo-servizio.domain.com/it OR
new-service.domain.com
nouveau-service.domain.com
nuovo-servizio.domain.com Looking forward to reading you!