The Language Explosion
Around the time your toddler reaches 18 months of age, you're in for a treat he'll begin learning words at an astonishing rate.
Development rates vary, of course, but generally a language explosion occurs around 18 months. At that time, most children start adding new words at an incredible rate, giving them a vocabulary of 1,000 to 2,000 words by the time they are two. At 18 months they also are likely to combine words into short phrases — "want juice," "no sleep," "go bye-bye."
Grammar, too, is rapidly acquired. Our brains seem to be naturally prone to, and capable of, the grammar and the organization that makes language work. By 24 and 30 months, children have a basic sense of their language's internal structure or grammar, usually placing pronouns, nouns, and verbs in the right order.
Kinds of Words
As vocabulary expands to include verbs and adjectives as well as nouns, language moves from naming objects into describing what they do and how they do it. This, in turn, sets the stage for using words in place of the objects they name. This is a very important development because it is the cornerstone of judgment, reasoning, managing impulses, and inhibiting action. Armed with the right words, a child who doesn't like big dogs needs only to be told that there is a "big dog" in the backyard at a neighbor's house to understand what awaits him should he venture out the back door.
All this makes it clear that the more a child wants to convey about his experience, the sooner his speech will develop. The urgency of first words is directly related to the tension created in the child over being understood. It literally feels good in one's mind and body to be understood, not simply in one's ears.
Even as adults we will talk "until blue in the face," referring to our failure to stop and breathe until we are understood. When at last we are understood, we relax physiologically. The toddler feels the same swings of passion under these circumstances.