1)      Because sound change is a mysterious aspect of change in language, we don’t really know how and why the phoneme [e:] changed to [i:] for example.

     2)      Neogrammarians’ basic axiom is that sound change is “regular” (sound laws have no exceptions). They tend to be dichotomous, they are non social in character and they recognize the importance of present dialects (spoken language) although they have written sources. 

     3)      The change depends on the degree of internal cohesion of the community, and change from outside. It has to be maintained by social acceptance and social pressure. 

     4)      Because we must consider the possibility that sound change is not triggered at this level: a sound change perceived by observes at the segmental level may be a secondary phenomenon.

     5)      Because sociolinguistics approaches do not give support to the idea of "blind necessity". According to them, dichotomies are very important to the sound change.

    6)      Lexical diffusion is both a phenomenon and a theory. The phenomenon is that by which a phoneme is modified in a subset of the lexicon, and spreads gradually to other lexical items. For example: /uː/ has changed to /ʊ/ in good and hood but not in food.

    7)      It means a displacement of one dialect by another which is socially dominant at some particular time. For example there is evidence from recordings of persons born around 1860 which can be interpreted as indicating that much New Zeland English in the 19^th century was southern British in type and that it was displaced by an Australasian type with some effects of mixing and residue.

    8)      The norms of language are maintained and enforced by social pressures. It is customary to think of these norms as standardizing norms. These norms manifest themselves at different levels of generality.

     9)      He means that, in a paper on /h/ - dropping, a change can persist as a variable state for seven or eight centuries without ever going to ‘completion’ in the traditional sense.

    10)   An innovation is an act of the speaker, while a change is manifestated within the language system. It is speakers and not languages that innovate. It must be speakers rather than languages who favour the new variants.

    11)  Because all sound change depends on a process of “borrowing”. Change is negotiated between speakers, who borrow new forms from one onther.

    12)  A sound to spread needs dialect contact (geographical and social contact) and the diffusion of changes through “borrowing”.    

    13)  Because standard languages are not normal languages, they are created by the imposition of political power, they are not explainable by reference to phenomena internal to the structure of language.

    14)   ‘Clean’ data are those who have already been largely normalized, while on the other hand ‘dirty’ data are the irregular and cahotic parts of the “data-base”, i.e. the whole linguistic Corpus.