Is English the easiest language?

All languages have a complex grammar David Crystal

To paraphrase Steven Pinker, we are born with the capacity to learn a language — regardless of how difficult it may appear in a text book. A child growing up in Japan will learn (spoken) Japanese as easily one in France will master French.

It is when learning a secondary language that we can compare the relative difficulty, though as the linguist David Crystal points out 'all languages have a complex grammar 

there may be relative simplicity in one respect (e.g., no word-endings), but there seems always to be relative complexity in another (e.g., word-position).

Nonetheless, it is true that the relative flexibility of English is very helpful for beginners.

What helps English language learners?

The most obvious advantage is that English is what linguists call a 'weakly inflected' language. It has a comparatively simple morphology (word formation). This means that the form of word changes less frequently than more inflected languages.

Put crudely, English language learners need to memorise fewer word formation rules than students of Latin, Russian, German or Ancient Greek.French nouns, for example, are either masculine or feminine and this dictates the article that precedes them le stylo, la maison (the pen, the house)

And though there are conventions these do not amount to a rulebook. The previous sentence ignored one in starting a sentence with a preposition - now standard practice in journalism.

Nor is there an English language academy, policing usage.

Esperanto v English

In contrast, Esperanto challenges all languages when it comes to structural simplicity. It has no grammatical gender, and nominal inflections. It also boasts regularised phonetics. 

Esperanto also has regularised phonetics - no cough to deal with or silent letters. Vocabulary is based on Indo-European languages, with much that is immediately familiar to the speakers of Romance languages.

Words, Words, Words

English may seem 'easy' but bear traps await. One is irregular verbs - see here. Another that causes great difficulty is the use of the direct article - fine to go to the prison not so welcome to go to prison. 

Then there is the sheer size of the English lexicon or vocabulary (those twenty volumes of the Oxford English Dictionary) and the vast number of phrasal verbs. Without getting into the technicalities a phrasal verb changes meaning by adding a preposition to the root verb. These are maddeningly illogical for English language learners - see here 

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