90. What is sociolinguistics?
Sociolinguistics studies relationships between language and various aspects of society. One major focus of sociolinguistics is the study of language variation, that is, the ways language differs across social settings.
 
91. What are language varieties and dialects?
Language variety is a broad term that can be applied to any language system. For example, entire languages such as English, Japanese, Flemish, and Malaysian can be referred to as language varieties. Language varieties also (and perhaps more commonly) refer to different forms of the same language. Such varieties are often called dialects. Dialects of a language may be associated with different geographical regions, for example, Michigan, Mississippi, or Los Angeles, as well as with various social groups defined by socioeconomic class, culture, and/or ethnicity. Thus, we speak of regional dialects and social dialects.
92. What are pidgins and creoles?
Two sorts of language varieties that do not fit typical language or dialect definitions are pidgins and creoles. These interesting varieties evolve as the result of contact between multiple languages. Pidgins, for example, develop when speakers from different languages need a common language for communication, such as for trade. Circumstances may not allow speakers to select one of their own languages as a lingua franca, or common language, so speakers create a system that blends various parts of their different languages. We often refer to these mixed language systems, or pidgins, as English-based, Portuguese-based, and so forth to indicate what language has supplied the bulk of the vocabulary to the pidgin. Examples of English-based pidgins include Tok Pisin, spoken in Papua New Guinea, and Cameroon Pidgin, spoken in Cameroon, Africa. These and other pidgins differ from "normal" language varieties in that they are simplified in their phonological, lexical, and structural features.
Pidgins are usually auxiliary languages; that is, pidgin speakers tend to have some other language as their "mother tongue" and typically use pidgins for other social functions. Often when the original need for the pidgin disappears, so does the pidgin. In some cases, however, the role of the pidgin greatly expands as a speech community acquires the pidgin as its primary language. When this occurs, the pidgin turns into something else--a creole. Structurally, creoles (e.g. the French-based Haitian Creole, the English-based Jamaican creole, and many others) are distinguished from pidgins by their larger vocabularies and more complex grammatical patterns.

93. What stages do children go through in acquiring a language?
If you have ever been around babies, you have undoubtedly noticed that they begin "vocalizing" right away. However, it is not until later that their utterances begin to reflect clearer linguistic features. At about six weeks, for example, babies begin cooing vowel sounds. Later, at roughly six months, children sound even more language-like as they begin babbling streams of consonants and vowels with patterned syllable structure (e.g. "babababa") as well as with intonation features of the language being learned. Thus, some of children’s babbles may sound a little like real sentences because of their melodies, or prosody.
Around one year, children reach a major milestone—the first word, or the one word stage. Although children’s early words may not sound exactly like adult words (e.g. "baba" for bottle), they nonetheless have real meaning for children. Early vocabularies tend to consist of concrete words describing things, people, and actions in the child’s immediate environment (e.g. "kitty," "daddy," "juice," "mommy," "go"), as well as social interactive words (e.g. "hi," "bye"). Children’s utterances at this time are often called holophrases because a single word may represent the meaning of an entire adult sentence. For example, "doggie?" with a rising intonation might mean "Is that a dog?"
As one might predict, the next major stage of language development is the two-word stage, beginning roughly around two years old. Here children begin to express relationships through language (e.g. "mommy shoe," "baby sleep," "teddy bed," "kick ball") as well as reflect awareness of basic syntactic structures in their language. For example, a child who says "kick ball" shows understanding, albeit unconscious, that verbs (e.g. "kick") go before direct object nouns (e.g. "ball") in English.
In their next stage of development, children begin to combine three or more words in sentences. This multi-word milestone is often called the telegraphic stage because the utterances children produce during this time sound like telegrams. Consider the following telegraphic sentences: "Katie walk school," "Jeremy need that," "Cathy build two house." What do you notice is missing from these sentences? Children during this stage tend to leave out function words, such as prepositions (e.g. the "to" in the first sentence), determiners, and auxiliary verbs, as well as affixes (e.g. the third person singular -s on "need" and the plural -s on "house"). These omitted function words and affixes are known as grammatical morphemes.