Here's a breakdown:
* Dutch is considered the closest to German, with a mutual intelligibility of around 60%. This means speakers of both languages can understand a significant portion of each other's language without prior knowledge.
* Frisian is also closely related to German, sharing many similarities in vocabulary and grammar. It's spoken in the Netherlands and Germany.
* Yiddish, a language heavily influenced by German, is spoken by Jewish communities around the world. It is distinct from German but shares many similarities.
* English, though seemingly far removed, also has significant influences from German, particularly in its vocabulary.
Other related languages include:
* Swedish
* Danish
* Norwegian
* Icelandic
It's important to note that "closest" is a relative term, and the degree of similarity depends on the specific criteria used for comparison.