Listen to the passage and fill in the blanks. Write down the answers with the numer of questions, for example "11. research".Research is defined as a serious study of a subject to (11)______ new facts or test a new idea. It is a careful consideration of study regarding a particular concern or problem using (12)________ methods. It involves logical reasoning and a systematic (13)________. Both must be followed by accurate data. By the (14)_______ of data, research can be classified into two types: primary research and secondary research. Primary research is based on (15)______ data. The research is (16)________ first hand to obtain data. It could be the record of an (17)_________, a survey or testing. Primary research is an expensive process for it consumes a lot of time to (18)________ and analyze data. While secondary research is relatively quick and easy because it is done with the data from (19)________ researches which have been analyzed and filtered already. Secondary research involves the (20)________ of past researches or comments on their findings.