this study investigated the functions, types and frequencies of code switching in the teachers and students discourse in elt classrooms. to this end, the participants of this study including two groups of teachers and students were selected. the first group of participants were two efl teachers teaching general english courses (at two different levels of proficiency) in an institutional program...

attempts have been made to study the thermodynamic behavior of 1,3 butadiene purification columns with the aim of retrofitting those columns to more energy efficient separation schemes. 1,3 butadiene is purified in two columns in series through being separated from methyl acetylene and 1,2 butadiene in the first and second column respectively. comparisons have been made among different therm...

cement is an essential ingredient in the concrete buildings. for production of cement considerable amount of fossil fuel and electrical energy is consumed. on the other hand for generating one tone of portland cement, nearly one ton of carbon dioxide is released. it shows that 7 percent of the total released carbon dioxide in the world relates to the cement industry. considering ecological issu...

abstract this study examined the relationship between noticing pronunciation and the improvement pronunciation by administering a 50 item story, as proficiency- test in order to investigate the effectiveness of noticing pronunciation on the improvement of pronunciation. accordingly 60 qualified students were selected and assigned to the two groups of experimental and control randomly, each gr...

abstract the present study was conducted to examine the effect of proficiency on students interaction while carrying out the grammar-based task(s) in collaboration. in particular, the study examines whether the level of proficiency affects the learners’ focus of attention to grammatical and lexical features. the study takes a further step and examines whether there is any difference in the use...

the main purpose of this study was to investigate any relationship between high school efl teachers metaphorical understandings of their role in class and their self-efficacy beliefs. teachers metaphors were elicited through two different prompts: one picturing what they believed a language teacher should be like in class, and the other demonstrating what they are actually like in class; such...

abstract the present study was conducted in order to investigate the impact of an integrated model of form-focused and task-based instruction on iranian efl learners vocabulary learning and retention.it also aimed to detect efl learners attitude towards the implementation of form-focused task-based vocabulary instruction in the classroom. in order to address the purposes of this study, a sampl...

boron nitride semiconducting zigzag swcnt, $b_{cb}$$n_{cn}$$c_{1-cb-cn}$, as a potential candidate for making nanoelectronic devices was examined. in contrast to the previous dft calculations, wherein just one boron and nitrogen doping configuration have been considered, here for the average over all possible configurations, density of states (dos) was calculated in terms of boron and nitrogen ...

armenias geopolitics and its historical experience have had a determining impact on the character of its foreign policy .present-day armenia is a small, landlocked country with _11,620 square miles area armenias landlocked nature makes it dependent on the benevolence of its neighbors for access to the outside world a fact that gives it a sense of isolation and vulnerability. as it was indic...

the extent to which written corrective feedback on linguistic errors can play a role in helping l2 writers improve the accuracy of their writing continues to be an issue of interest to researchers and teachers since truscott (1996) mounted a case for its abolition. while there is growing empirical evidence that written corrective feedback can successfully target some types of linguistic error (...