Why and how English and German is related?
In the same way that French, Italian and Spanish are Romance or Romantic languages, meaning they all come from the Latin (Rome), English is a Germanic language. It has to do with the origins of the languages. Germanic Languages subfamily of the Indo-European family of languages, spoken by about 470 million people in many parts of the world, but chiefly in Europe and the Western Hemisphere. All the modern Germanic languages are closely related; moreover, they become progressively closer grammatically and lexically when traced back to the earliest records. This suggests that they all derive from a still earlier common ancestor, which is traditionally referred to as Proto-Germanic and which is believed to have broken from the other Indo-European languages before 500 Although no writing in Proto-Germanic has survived, the language has been substantially reconstructed by using the oldest records that exist of the Germanic tongue.
