The advent of the notional-functional syllabus with its emphasis upon the communicative aspects of language as opposed to its structutal features gave fresh impetus to the construction of concept categories suitable for learners of specialist subjects. In addition, it is recognised that learners must be familiar with not only technical terminology but also with those common exppessions that make up the major part of the sentence (e.g. verbs, nouns, prepositions) and which carry essential meanings. There are some exptessions or concepts that occur as frequently as they are misused. This is often due to the fact that they are read passi-vely. A student who has met them in the course of a scientific article may be able to recognize them.
The following list for the benefit of science students and researchers has been prepared in the hope that they will profit in a very practical way from a study of these expressions. This is important for the logical reason tbat language is concerned with concepts. To be able to use its linguistic expression is to apply or 'possess' the concept.