3.5.3 vocabulary tests
    (a) vocabulary pre-test
    to measure the participants'knowledge of the target words prior to the study, a list of 25 words (10 target words with 15 other words) was designed for the participants to self-report their knowledge of the vocabulary items at the initial phase of the study. the participants were asked to circle a number on a five-point scale to indicate how well they knew the word (e. g.4=i know the word well and can use it correctly; 0=i do not know the word at all). table 7 gives an example of the vocabulary pre-test.
    table 7 example of the vocabulary pre-test
    to make sure that the participants' answers to the test were reliable, the target words were tested along with 15 distracter words of different levels. table 8 shows the distribution of words in each level according to the classification of cobb (2005).
    table 8 statistics of words in each level
    (source: cobb, 2005)
    (b) vocabulary posttests
    after the participants finished each listening task, three types of vocabulary posttests (a form test, a reception test, and a production test) were administered to check the students'incidental acquisition of the 5 target words from each listening task. five questions were designed in each test and the highest possible score of each test was 5 marks. the participants got 1 mark with each correct answer in the test.
    form test
    in the form test, each of the 5 target words was put in a word list with 4 distracters, i. e., words similar in form. the participants were asked to circle the target word from the word list and then tell how certain they were about the one they circled by entering a percentage in the box after the word list.
    example: declare-decline-declaim-incline-reclaim
    reception test
    to check if the participants were able to recognize the meaning of the target words, following the example of read's (2000) matching items, a reception test was designed. the participants were asked to choose 3 words (1 target word with 2 distracters) from the left column and properly match their numbers with their synonyms or definitions in the right column. for example:
    1. region
    2. atlas 5 set of bones in the body
    3. statue 1 part of a country
    4. cell 4 smallest part of living things
    5. skeleton
    (source: read, 2000, p.172)
    production test
    in the production test, 5 sentences were chosen from the listening text and presented with the 5 target words removed. to measure their ability to produce the words, the participants were asked to fill in the blanks with what they heard from the listening texts.
    example:
    but we ended with stronger sales than we expected and i am very for next year.
    to avoid inter-crossing information, thethree vocabulary posttests abovewere delivered separately to the participants.