<strong>ملخص الدراسة:</strong>

Fixed expressions like idioms , are not usually taught , although they are essential for learning progress . This is because they are considered by many teachers of foreign languages to be the most difficult aspect of vocabulary not only for the learners to master but for the teachers of foreign language too .This is , to a large extent , true and so most teachers and foreign language learners encounter difficulties in decoding idioms . This paper explores the hypothesis that there may be a considerable degree of difficulty in comprehending and using idiomatic expressions which share their figurative meaning and the same underlying structure . Some informant testing was conducted to see whether native speakers of Arabic would be able to “ make sense “ of some idiomatic expressions . Equally , the test was in a form of exercise the purpose of which was to see whether teachers of English are able to decode the figurative meaning of idioms in a foreign language , thus contributing to the overall meaning of these expressions .