Launchpad currently recommends translating glibc in Ubuntu Zesty.

Template "libc" in Ubuntu Zesty package "glibc"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 1476 1476 0 0
Dakota 100.00  100.0% untranslated 1476 1476 0 0
Hawaiian 100.00  100.0% untranslated 1476 1476 0 0
Inuktitut 100.00  100.0% untranslated 1476 1476 0 0
Lakota 100.00  100.0% untranslated 1476 1476 0 0
Ojibwe 100.00  100.0% untranslated 1476 1476 0 0
Spanish 002.44  97.5609756098% translated  2.43902439024% untranslated 36 36 0 342 342 2017-06-07 08:42:54 UTC 2017-06-07 Paco Molinero
Tlingit 100.00  100.0% untranslated 1476 1476 0 0
Yiddish 100.00  100.0% untranslated 1476 1476 0 0
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Key to this table: “Unchanged” means Translated
and “untranslated” means just that, Untranslated

Other versions of glibc in Ubuntu