What are the easiest languages to learn and the hardest to learn?

Answer 1

For an English speaker? 

Easiest : (Lowland) Scots or Frisian. 

Hardest : the usual examples are Northwest Caucasian languages (up to 80 distinct consonants and only 2 or 3 vowels), Khoisan languages of southern Africa (up to 87 distinct click consonants) and Southern Athabaskan languages like Navajo and Apache (very few outsiders ever managed to become fluent).

Answer 2

In general, Esperanto is the easiest (but still takes work).

for native speakers of English, the hard popular ones are Japanese, Korean, Arabic and all types of Chinese.

Navaho and Uzhbyk (?) are even harder

Answer 3

It depends on people, their ability to learn but not only, since motivation and the time spent learning it count too. 

Answer 4

For a teen or adult, Spanish and Italian are easy. 

For a small child, English is easier.  

They say Navajo and Inuit are the hardest.