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From text to speech: The MITalk system
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then to the root and leftmost suffix combined. The process continues with one
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more suffix adjoined to the string under consideration before each cycle begins,
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until the end of the word is reached. This cyclic phase is devoted solely to the
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placement of primary stress. Unless otherwise noted, prefixes are considered part
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of the root.
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The second, noncyclic phase includes the application to the entire word of or-
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dered rules and reduces all but one. of the primary stress marks to secondary or
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ZETO Stress.
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The stress marks used here are ’ for primary stress and " for secondary
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stress.
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In the following sections, stress placement rules will be given both as for-
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mulas and in descriptive (nonsymbolic) form. Each rule which contains more than
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one case is broken down into cases for which brief descriptions and examples are
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given. It is important to note that a particular case applies only if the rules for pre-
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vious cases have not applied, i.e., a maximum of one case per rule is applicable.
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The subrules in each case are mutually exclusive. The rules are listed in the order
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in which they apply and are marked either cyclic or noncyclic.
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In this context, syllable means a vowel followed by any number of consonants
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(including none). Weak syllable means a.short (or nontense) vowel followed by, at
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most, one consonant before the next vowel. The words vowel and consonant them-
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selves denote the vocalic and nonvocalic phonetic segment labels output from the
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letter-to-sound conversion stage, rather than the letters in the original word. In the
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examples, Klatt symbols are used to represent the segment labels. The short
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vowels are: AA, EH, IH, AO, UH, AH, AX, AE, and 1X. Long vowels are: EY, IY,
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AY, OW, UW, OY, and Aw. |
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Each formula is a phonetic segment string pattern matching expression. The
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symbols used in the formulas are defined as follows:
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C matches a single consonant. Sub- and superscripts denote lower and upper
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bounds, respectively, on the number of replications of the preceding term
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(usually C). For example, Cy matches any number of consecutive con-
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sonants (including none) while C% matches one or two consonants.
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V matches a single vowel.
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X and Y match segment strings of any length (including null, unless noted
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otherwise).
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Brackets [ ] denote the association of one or more features with a vowel. The fea-
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