About 85% of words in the English language are from three languages – Germanic, French and Latin. 12% are from Greek and other minor languages like Chinese and Japanese. About 4% are proper names.
Different languages had influence on English at different periods in history. Latin was the language of the Church. French came with the Norman conquest, etc.
Finally, these numbers are counting types (dictionary-like count of entries of words) and not actual usage of words (frequencies of individual words).
Lexicogrammar is not a word you hear much but those of a certain following – cognitive linguists, functional grammarians, etc – use this word to describe what is traditionally call vocabulary and grammar as one system rather than being two separate systems.
As a researcher in prepositions this is a big deal. It means I (can) treat prepositions as vocabulary, requiring them to be learnt by students when before they were and still are somewhat relegated to the category of grammar. Vocabulary and grammar should not be studied separately. Vocabulary are not individual words to be studied, or looked up when you don’t know the word. Vocabulary only have full function within a sentence, and shine bright within the context of use within communication. Certainly, in Saussurean linguistics the signifier/signified duality of words are an important and enlightening feature. But words are best understood in communicative units, namely sentences. And Saussure will not have argued against that. In fact he argued for it.
Undoubtedly dictionaries are useful tools. But they generally push the learner to think of words as separate objects with separate meanings. Good dictionaries will give plenty of examples of usage but students will generally use the cheapest or most handy dictionary at hand. Today this is the smartphone dictionary and translator. Rarely do they give examples. And for most of the time they give one translation to one word, suppressing the multiple nuanced (often schematically-related) meanings that most words have. I shall talk about this point in another post.
We have truly come to understand that language is usage in the last thirty years.
So when someone says that they disapprove of loanwords coming into their language they are really not understanding this point. They are coming from the Old School which thinks grammar (and vocabulary) is perscriptive, not descriptive.
English is itself a language built upon loanwords. The language has been borrowing words from the very beginning from Latin, Old Norse, French and Greek just for starters. And in this day and age it borrows from whatever language it comes into contact.
Why languages do so is because new ideas come in faster than words can be created. Also where the idea comes from also influences its adoptive form. So really when people are complaining about the loanwords they are complaining about influences that maybe seen as from outside the culture.
One should not be surprised that such insularity still exists in this day and age.
It seems the average non-native speaker of English only has a vocabulary size of about 4,500 words. And over half of these learners will have a vocabulary size of greater than 7,826 words. This is a somewhat depressing picture for language learners considering the worst of native speaker adults still will have a minimum size of 20,000 words with the high end at 35,000 words.
So what is the best way for non-native speakers to increase their vocabulary size? According to these statistics from testyourvocab.com the biggest factor is out-of-class activities. The more you do outside of the classroom the broader your vocabulary. Otherwise three years living abroad will do the trick. Even then the non-native speaker will only have 10,000 words (that is equal to the vocabulary size of an 8 year old native speaker). To reach 18,000 words over 10 years of living abroad is necessary.