Launchpad currently recommends translating glibc in Ubuntu Cosmic.

Template "libc" in Ubuntu Cosmic package "glibc"

Language Status Untranslated Need review Changed Last Edited By
Cherokee 100.00  100.0% untranslated 1462 1462 0 0
Dakota 100.00  100.0% untranslated 1462 1462 0 0
Hawaiian 100.00  100.0% untranslated 1462 1462 0 0
Inuktitut 100.00  100.0% untranslated 1462 1462 0 0
Lakota 100.00  100.0% untranslated 1462 1462 0 0
Ojibwe 100.00  100.0% untranslated 1462 1462 0 0
Spanish 005.20  94.8016415869% translated  5.19835841313% untranslated 76 76 0 323 323 2017-08-21 05:35:17 UTC 2017-08-21 Adolfo Jayme
Tlingit 100.00  100.0% untranslated 1462 1462 0 0
Yiddish 100.00  100.0% untranslated 1462 1462 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