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 002.91  97.0867208672% translated  2.91327913279% untranslated 43 43 0 342 342 2016-09-03 06:32:01 UTC 2016-09-03 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