Scientific English and Thai students : a study of the comprehensibility of complex structures : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Education at Massey University
This study attempted to examine (i) the relationship between Thai science students' comprehension of English complex structures and their reading comprehension of scientific English passages, (ii) the patterns among comprehensibility levels of complex structures for good and pool readers and (iii) the differences in the comprehensibility of complex structures within given types for good and poor readers, taken separately. The sample comprised 190 subjects who were drawn from five different Faculties at Khon Kaen University -- Medicine, Nursing, Science, Agriculture and Education. Four tests were constructed -- two measuring comprehension of scientific English, two measuring comprehension of three types of complex structures, viz., complements, comparatives and relatives. On the basis of cloze reading scores, 40 good readers and 43 poor readers were identified. Their structure comprehension scores were analyzed and compared. The results revealed that comprehension of English complex structures and reading comprehension of scientific English passages were positively related. When comprehensibility levels of complex structures were examined for patterns and when patterns characteristic of good and poor readers were compared, the results revealed a group of structures easy for both groups and another group of structures which tended to be relatively difficult for both groups. Easy structures seemed to share several general features notably the presence of particular types of surface cues in the surface structures, the presence of all surface elements and overt rather than covert ordering of surface elements within clauses. Difficult structures, on the other hand, displayed different types of surface cues or had surface cues absent from the surface structures. Moreover in such difficult structures, not all surface elements were present. It was also found that there were differences in the comprehensibility levels of complex structures within the different types. Again the presence or absence of surface cues seemed to affect sentence comprehensibility. The easier structures within the different types tended to contain the surface elements required to understand the sentence. The position of the relative clause seemed also to have an effect on the comprehensibility level of relative sentences. Right-branching relative clauses seemed to be more comprehensible than centre-embedded relative clauses. Finally the data revealed that good readers comprehended complex structures significantly better than did poor readers in most of the structures investigated. Their comprehension of two complex structures, however, was found not significantly different. They were (i) Non-finite (to-infinitive) object complement and (ii) Comparison of inequality where than is absent. Some explanation of the results was attempted and some educational implications were drawn.