Detailed answer
Alternate links with hreflang describe equivalent language versions.
Each target should contain the indicated language and correspond to the same content. Keep the alternate set consistent across those pages. The links describe translations that exist; they do not translate content or justify pointing all languages to unrelated homepages.
Example
<link rel="alternate" hreflang="en" href="https://example.com/en/html/">
<link rel="alternate" hreflang="hi" href="https://example.com/hi/html/">
Understanding the behavior
Hreflang describes alternate versions for languages or regions, while lang describes the language of the current document. Alternate pages should identify themselves and link back consistently. Use actual equivalent pages rather than pointing every locale to a single untranslated page.
Practical implementation notes
Check the full set of alternate links on every participating version. Canonicals and language alternates should agree about the intended pages, and every referenced URL should be publicly accessible.
How to check it
Check both alternate links and verify the actual content language of each destination.
Expected result
Each language target is a matching translation rather than an unrelated page.
Watch out: Check that every alternate page actually exists in the stated language.
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