Chapter intensive Reading Introduce the topic

1.2 Read the section with the students
It is worth noting that the period in which a child acquires his/her first language is called “Critical Period”, and if the child does not acquire the language during this period, language acquisition becomes language learning. Accordingly, the term “Second Language Learning” (SLA) emerges to refer to the language that a child learns after his/her first language acquisition process is/not completed. In SLA, a person is cognitively affected by factors as he/she need to exert cognitive effort in order to learn this language, unlike the first language acquisition process, which is spontaneous and discrete, and there is room for any cognitive effect (Leaver et al., 2005). So, the difference between first language acquisition and second or foreign language learning is that acquisition takes place autonomously and spontaneously at an early age, while learning - which involves direct instruction and guidance - takes place when a child has/not already acquired their first language. In language learning whether it is second or foreign, cognitive factors play a big role. Different types of word stress are distinguished not only according to its physical (acoustic) nature and degree, but also according to its position in different words of the language. "From this point of view two types of word stress are distinguished: fixed and free.
a) In languages with fixed word stress the position of stress is the same in all the words. For instance, in Czech and Lettish the main stress falls on the first syllable of each word and grammatical form of а word; in French, stress is tied to the last syllable of each word; in Polish, it falls on the prefinal syllable of all words and their grammatical forms.
b) In languages with free word stress the primary stress may fall in different words on any syllable. For example in Russian: к`омната, раб`ота, матем`атика, преподав`атель, машиностро`ение, окн`о; in English: `mother, ig`nore, соn`sideРration, ciga`rette.
Within frее word stress two subtypes are distinguished on morphological grounds: constant and shifting.
a. А constant stress is one which remains on the same morpheme in different grammatical forms of а word or in different derivatives from one and the same root. For example: ``wonder - `wondering - `wonderful - `wonderfully.
b. А shifting stress is one which falls on different morphemes in different grammatical forms of а word or in different derivatives from one and the same root,
Stress is also shifted under the influence of rhythm. For instance, Ber`lin - `Berlin `streets, Chi`nese - a `Chinese `lantern; un`known - an `unknown writer - The `writer is `quite un`known.
Similarly, accent can be used at the phrasal level to distinguish sequences identical at the segmental level (e.g. `light housekeeping' versus `lighthouse keeping' or `blackboard' versus `black board'). Finally, accent can be used at the sentence level to draw attention to one part of the sentence rather then another (e.g. `What did you sign?' `I signed a contract to do some light housekeeping.' versus `Who signed a contract?' `I signed a contract to do some light housekeeping.')" [10; 54].
On the auditory level a stressed syllable is the part of the word which has a special prominence. It is produced by a greater loudness and length, modifications in the pitch and quality. The physical correlates are: inten sity, duration, frequency and the formant structure. All these features can be analyzed on the acoustic level. "Word stress can be defined as the singling out of one or more syllables in a word, which is accompanied by the change of the force of utterance, pitch of the voice, qualitative and quantitative characteristics of the sound, which is usually a vowel. In different languages one of the factors constituting word stress is usually more significant than the others. According to the most important feature different types, of word stress are distinguished in different languages.
1) If special prominence in a stressed syllable or syllables is achieved mainly through the intensity of articulation, such type of stress is called dynamic, or force stress.
2) If special prominence in a stressed syllable is achieved mainly through the change of pitch, or musical tone, such accent is called musical, or tonic. It is characteristic of the Japanese, Korean and other oriental languages.
3) If special prominence in a stressed syllable is achieved through the changes in the quantity of the vowels, which are longer in the stressed syllables than in the unstressed ones, such type of stress is called quantitative.
4) Qualitative type of stress is achieved through the changes in the quality of the vowel under stress" [4; 51].
English word stress is traditionally defined as dynamic, but in fact, the special prominence of the stressed syllables is manifested in the English language not only through the increase of intensity, but also through the changes in the vowel quantity, consonant and vowel quality and pitch of the voice.
From the viewpoint of phonology, the main function of stress is to provide a means of distinguishing degrees of emphasis or contrast in sentences (sentence stress), as in The big man looks angry; the term contrastive stress is often used for this function. Many pairs of words and word sequences can also be distinguished using stress variation (lexical stress or word stress), as in the contrast between An increase in pay is needed and I'm going to increase his pay or the distinction between `black `bird and `black-bird.<sup>4</sup>
The analytical question here, which attracted a great deal of attention in the middle decades of the twentieth century, is how many degrees of stress need to be recognized in order to account for all such contrasts, and to show the interrelationships between words derived from a common root, such as `telegraph, tele`graphic and te`legraphy.
From а purely phonetic point of view polysyllabic word has as many degrees of prominence as there are syllables in it. А. С. Gimson gives the following distribution of the degrees of stress in the word "ехаmination":
The most prominent syllable is marked by figure 1, the second degree of prominence - by figure 2, then goes 3, and so on. However, not all these degrees of prominence are linguistically relevant.
The syllables bearing either primary or secondary stress are termed stressed, while syllables with weak stress are саlled, somewhat inaccurately, unstressed.
These contrasts are, however, demonstrable only on words in isolation, as in the compound elevator operator - one of several such phrases originally cited to justify analyses of this kind.
Alternative views recognized different kinds and degrees of stress, the simplest postulating a straight stressed v. unstressed contrast, referring to other factors (such as intonation and vowel quality) to explain such sequences as elevator operator. "In distinctive feature theories of phonology, the various degrees of stress are assigned to the syllables of words by means of the repeated application of rules (such as `lexical', `compound' and `nuclear' stress rules). Some analysts maintain there is a distinction to be made between linguistic contrasts involving loudness (which they refer to as `stress') and those additionally involving pitch (which they refer to as "accent"). All the examples given above, they would argue, are matters of accent, not stress, because contrasts in pitch variation are normally involved. Similar problems arise in the analysis of tone languages.
In the context of rhythm studies, the notion of a stress-timed language is often cited, i.e. one where the stresses fall at roughly regular intervals within an utterance. In analyzing such a language in this way, the notion of silent stress is sometimes invoked. The reason is to handle cases where the omission of a stressed syllable in colloquial speech can none the less be `felt'; a regularly cited case in the abbreviated version of thank you, which is said to be the unstressed residue of an unspoken stressed + unstressed combination. A sequence of syllables constituting a rhythmical unit, containing one primary stress, is known as a stress group. In metrical phonology a stress-foot is a string containing as its first element a stressed syllable, followed by zero or more unstressed syllables symbolized by У. The most prominent element in the stress foot is called the head. It should be noted that `foot', in this context, refers to an underlying unit, whose phonetic interpretation varies according to the theoretical approach.
Destressing, in this approach, is a rule, which eliminates stresses produced by foot construction. When two stressed syllables are immediately adjacent, the situation is described as stress clash. Speakers have a tendency to avoid stress clash; for example, the word thirteen is normally stressed on the second syllable, but in the phrase thirteen men, the stress shifts to the first syllable" [13; 456].
In languages, stressed and unstressed syllables differences can be distinguished by differences in length, pitch, loudness, or vowel quality. As the chart below shows, English makes use of all these distinctions. See table 1.2.
Table 1.2. Characteristics of levels of stress in words
Now, wedistinguished the fact: if а word contains more than one syllable, the relative prominence of those syllables differs. There may be one prominent syllable in а word as compared with the rest of the syllables of the same word (im`portant), or two equally prominent syllables (`misbe`have), or two unequally prominent syllables (е`xami`nation), or more than two prominent syllables (`unre`lia`bility). Such syllables are said to be stressed, but in every unique way. In the context of rhythm studies, the notion of a stress-timed language is often cited, i.e. one where the stresses fall at roughly regular intervals within an utterance. In analyzing such a language in this way, the notion of silent stress is sometimes invoked. The reason is to handle cases where the omission of a stressed syllable in colloquial speech can none the less be `felt'; a regularly cited case in the abbreviated version of thank you, which is said to be the unstressed residue of an unspoken stressed + unstressed combination. A sequence of syllables constituting a rhythmical unit, containing one primary stress, is known as a stress group. In metrical phonology a stress-foot is a string containing as its first element a stressed syllable, followed by zero or more unstressed syllables symbolized by У. Destressing, in this approach, is a rule, which eliminates stresses produced by foot construction. When two stressed syllables are immediately adjacent, the situation is described as stress clash. Speakers have a tendency to avoid stress clash; for example, the word thirteen is normally stressed on the second syllable, but in the phrase thirteen men, the stress shifts to the first syllable". Although there is no cognitive influence at the stage of first language acquisition, or what is known as the critical period hypothesis, Troike (2006) points out that there are other factors affecting the individual's first language acquisition during the “Critical Period Hypothesis (CPH). Robinson (2013) explains that the "critical period hypothesis" is the period in which the individual is exposed to their mother tongue for the first time. According to this hypothesis, first exposure to a language that takes place within the critical period results in normal levels of attainment in the case of first language (L1) acquisition and (in most cases) native like levels of attainment in the case of second language (L2) acquisition. However, if first exposure to a language takes place after the critical period, the end result will be non-normal/non-native like in the case of L1 and L2 learning, respectively.