learning a second or foreign language requires the manipulation of four main skills, namely, listening, reading, speaking, and writing which lead to effective communication. it is obvious that vocabulary is an indispensible part of any communication, so without a vocabulary, no meaningful communication can take place and meaningful communication relies heavily on vocabulary. one fundamental fac...

abstract this study investigates the teachers’ correction of students’ spoken errors of linguistic forms in efl classes, aiming at (a) examining the relationship between the learners’ proficiency level and the provision of corrective feedback types, (b) exploring the extent to which teachers’ use of different corrective feedback types is related to the immediate types of context in which err...

introduction acetic acid bacteria are large group of obligate aerobic gram negative bacteria with the ability to oxidize ethanol to acetic acid (1). they are widely distributed in natural habitats and classified in family acetobacteraceae. members of this family are useful in industrial production of vinegar(2). acetic acid bacteria (aab) can use substrates as glucose, ethanol, lactate or glyc...

abstract although music possesses some kind of power and using it has been welcome by many students in language classrooms, it seems that they take a non-serious image of the lesson while listening to songs and they may think that it is a matter of fun. the main objective of the present study was to investigate whether learning a foreign language through musical texts (songs) can have an impac...

chapter one is devotod to collect some notion and background informations, which are needed in the next chapters. it also contains some important statements which will be proved in a more general context later in this thesis. in chapter two, we show that if the marginal factor-group is of order np1...pk,n>1, then we obtain a bound for the order of the verbal subgroup. also a bound for the bear-...

abstract al- muntazam by ibn al -jawzi is one of the greatest the book ancient book of texts on history of islam in the 6th century.it is very important one;because of including rare reports which are not found any where.in addition to historical reports,his outlook , in which embodies information on mythologies, milal wa nihal (sects and creeds), geography, and political, social and religiou...

due to the limiting workspace of parallel manipulator and regarding to finding the trajectory planning of singularity free at workspace is difficult, so finding a best solution that can develop a technique to determine the singularity-free zones in the workspace of parallel manipulators is highly important. in this thesis a simple and new technique are presented to determine the maximal singula...

nowadays, air pollution is a global problem that has had significant growth by technology development, population growth andindustrial development. industrial development brought natural resources deterioration, more manufacturing products, and more environmental pollutants. if pollutant won’t be controlled, human-being and wildlife will face the critical risks. significant release and critical...

the major purpose of this study was to develop the translation teacher competency test (ttct) and examine its construct and predictive validity. the present study was conducted in two phases: a qualitative phase as well as a quantitative phase. in the first phase of the study, the author attempted to find out the major areas of competency required for an academic translation teacher. the second...

reinsurance is widely recognized as an important instrument in the capital management of an insurance company as well as its risk management tool. this thesis is intended to determine premium rates for different types of reinsurance policies. also, given the fact that the reinsurance coverage of every company depends upon its reserves, so different types of reserves and the method of their calc...