The phrase in the hierarchy of language units Contents Introduction

Conclusion
A hierarchical analysis of sentences into their constituent parts gives us a better understanding of the relationship among them. Functional grammar relates grammatical catagories to the communicative functions which they serve. These functions are seen to operate at different levels of organization in the language. This implies segmental principle of organization, in which larger units may be seen as being formed from smaller units and smaller units being combined to form the larger units. It can be seen from the above analysis that words and groups perform different functions at different levels. A group, at times, functions as a word. Sometimes addition of a morpheme ‘en’ causes a word to behave in a way which is quite different to its characteristic behaviour of the class to which it belongs, .e.g., the word sunken. The phenomenon whereby a group actually functions as a word is known as Rankshift or Embedding. This means that a unit of a certain complexity behaves in terms of its function in the total structure of the sentence as if it were a unit of a “lower” rank. Rankshift embedding is very common in English language, and there are many instances where groups of words may function as a single item. There are many phrases such as “out- of- the way”,”ready -to- wear”, “made to measure” etc. which can be interpreted as single items. There are many approaches to grammar. The prescriptive approach to grammar categorizes words into different classes. The descriptive approach attempts to describe the regular structures of the language as it is used, not according to some point of view of how it should be used. It is the descriptive approach to grammar which has led the grammarians to concentrate on the functions performed by different structures in a sentence.Having a better understanding of the functions of different structures in a sentence, helps us improve our grammatical competence which in turn improves the communicative competence of a speaker. Functional grammar hence, a key to communicative success. “Communicative competence can be defined, in terms of three components, as the ability to use the L2 accurately, appropriately, and flexibly. The first component is grammatical competence which involves the accurate use of words and structures in the L2.” (Yule, The study of language, p. 197) .Although it is possible to view sentences as hierarchically structured, this structure appears mainly as a side effect of exhaustively analysing the sentence by dividing it up into its parts, subparts, sub-subparts, etc. Psychologically, such hierarchical (de)composition is not a fundamental operation. Rather, considerations of simplicity and evolutionary continuity force us to take sequential structure as fundamental to human language processing. Indeed, this position gains support from a growing body of empirical evidence from cognitive neuroscience, psycholinguistics and computational linguistics.
This is not to say that hierarchical operations are non- existent, and we do not want to exclude their possible role in language comprehension or production. However, we expect that evidence for hierarchical operations will only be found when the language user is particularly attentive, when it is important for the task at hand (e.g. in meta-linguistic tasks) and when there is little relevant information from extra-sentential/linguistic context. Moreover, we stress that any individual demonstration of hierarchical processing does not prove its primacy in language use. In particular, even if some hierarchical grouping occurs in particular cases or circumstances, this does not imply that the operation can be applied recursively, yielding hierarchies of theoretically unbounded depth, as is traditionally assumed in theoretical linguistics. It is very likely that hierarchical combination is cognitively too demanding to be applied recursively. Moreover, it may rarely be required in normal language use. To conclude, the role of the sequential structure of language has thus far been neglected in the cognitive sciences. However, trends are converging across different fields to acknowledge its importance, and we expect that it will be possible to explain much of human language behaviour using just sequential structure.Thus, linguists and psychologists should take care to only invoke hierarchical structure in cases where simpler explanations, based on sequential structure, do not suffice.We would like to thank Inbal Arnon, Harald Baayen, Adele Goldberg, Stewart McCauley and two anonymous referees for their valuable comments. S.L.F. was funded by the EU 7th Framework Programme under grant no. 253803, R.B. by NWO grant no. 277-70-006 and M.H.C. by BSF grant
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