Language acquisition.

Language acquisition is one of the central topics in cognitive science. Every theory of cognition has tried to explain it; probably no other topic has aroused such controversy. Possessing a language is the quintessentially human trait: all normal humans speak, no nonhuman animal does. Language is the main vehicle by which we know about other people's thoughts, and the two must be intimately related. Every time we speak we are revealing something about language, so the facts of language structure are easy to come by; these data hint at a system of extraordinary complexity. Nonetheless, learning a first language is something every child does successfully, in a matter of a few years and without the need for formal lessons. With language so close to the core of what it means to be human, it is not surprising that children's acquisition of language has received so much attention.

Human language is made possible by special adaptations of the human mind and body that occurred in the course of human evolution, and which are put to use by children in acquiring their mother tongue. t direction.
"Language acquisition does not require extensive use of conscious grammatical rules, and does not require tedious drill." Stephen KrashenStephen Krashen

"Acquisition requires meaningful interaction in the target language - natural communication - in which speakers are concerned not with the form of their utterances but with the messages they are conveying and understanding." Stephen Krashen

"The best methods are therefore those that supply 'comprehensible input' in low anxiety situations, containing messages that students really want to hear. These methods do not force early production in the second language, but allow students to produce when they are 'ready', recognizing that improvement comes from supplying communicative and comprehensible input, and not from forcing and correcting production." Stephen Krashen

"In the real world, conversations with sympathetic native speakers who are willing to help the acquirer understand are very helpful." Stephen Krashen.

How do children acquire language? Do parents teach their children to talk?

No. Children acquire language quickly, easily, and without effort or formal teaching. It happens automatically, whether their parents try to teach them or not.
Although parents or other caretakers don't teach their children to speak, they do perform an important role by talking to their children. Children who are never spoken to will not acquire language. And the language must be used for interaction with the child; for example, a child who regularly hears language on the TV or radio but nowhere else will not learn to talk.
Children acquire language through interaction - not only with their parents and other adults, but also with other children. All normal children who grow up in normal households, surrounded by conversation, will acquire the language that is being used around them. And it is just as easy for a child to acquire two or more languages at the same time, as long as they are regularly interacting with speakers of those languages.
The special way in which many adults speak to small children also helps them to acquire language. Studies show that the 'baby talk' that adults naturally use with infants and toddlers tends to always be just a bit ahead of the level of the child's own language development, as though pulling the child along. This 'baby talk' has simpler vocabulary and sentence structure than adult language, exaggerated intonation and sounds, and lots of repetition and questions. All of these features help the child to sort out the meanings, sounds, and sentence patterns of his or her language

The first sounds a baby makes are the sounds of crying. Then, around six weeks of age, the baby will begin making vowel sounds, starting with aah, ee, and ooh. At about six months, the baby starts to produce strings of consonant-vowel pairs like boo and da. In this stage, the child is playing around with the sounds of speech and sorting out the sounds that are important for making words in his or her language from the sounds that aren't. Many parents hear a child in this stage produce a combination like "mama" or "dada" and excitedly declare that the child has uttered his or her first word, even though the child probably didn't attach any meaning to the 'word'.

 

When they start talking?

The child distinguishes the voice of his mother from birth
The child has to reach physical maturity earlier importantly, has to perceive and produce speech sounds and relate to other human beings and understand the world around him, and from there begin to be prepared to learn to speak.

The baby at birth takes a while for it to carry out a physiological adjustment to the environment in which they will live and who will have to get used.

It is a stage in which the baby is not used to postnatal life. During this period remains dormant most of the time. Even from birth, differentiate human sounds and recognize the significant voices for them.
How the child is progressing at this stage?
  From birth to 10 or 13 months are in what is known as prelinguistic phase of language development:
During the first month the baby is moving very rapidly with each week that passes. The first sounds of a baby is crying and vegetative sounds such as coughing and sneezing.
At this stage, pay attention and react to sounds, though the same discrimination occurs later.

8 weeks beginning to see the world around them in a more direct and discriminating. Make vowel sounds called cooing sounds that are repeated continuously when the babies are happy, for example, "aaaaach."
At 16 weeks or less begins babbling. The baby buzz, coos, laughs and add consonant sounds to their repertoire: they combine vowels and consonants and frequently repeated, for example, "mamamama", "Papapapá", etc, may seem like they are words, but do not convey any meaning. All this is done with the oral appliance is subsequently going to allow articulated speech.
In the period from 6 to 10-11 months, the baby screams and hums. Can produce alternating vowels and consonants strings. This is indicating that the oral apparatus is becoming more flexible and is producing an improvement in the muscles that govern speech. It is a stage that already use gestures and other nonverbal responses to communicate.