Answer
Language acquisition takes place most rapidly during a child’s 1-2 years.
Explanation
By six months, babies are able to differentiate between different sounds and their rhythm. They start babbling which is the first sign that they are learning the language.
In between 1 to 2 years (12 - 24 months), A child is able to attach meanings to words. He is able to respond to his parent's . He recognises the difference between nouns and verbs. He tries to mimic words as much as possible. He knows the right order of words in a sentence and he tries to speak words instead of using his gestures. By the end of 2nd year the child begins speaking in complete sentences.