4.2 research questions
    the main study aims to find answers to the following four research questions:
    research question one: what effects do different listening conditions have on learners' listening comprehension and incidental vocabulary acquisition?
    the four different listening conditions are:
    (a) when they listen to the texts just once;
    (b) when they listen to the texts three times;
    (c) when they engage in a schema raising activity before listening to the texts three times; and
    (d) when they engage in an inferencing strategy training before listening to the texts three times?
    research question two: what is the relationship between learners' listening comprehension and incidental vocabulary acquisition from listening tasks under the same conditions as above?
    research question three: what is the relationship between learners' metacognitive listening awareness and their listening comprehension from listening tasks under the same listening conditions as above?
    research question four: what is the relationship between learners' metacognitive listening awareness and incidental vocabulary acquisition from listening tasks under the same conditions as above?