本讲为2006年下半年新的教学内容，请对照教材、练习册和语法书听录音！       1.       Data from previous animal experiments is used to develop a computer model which will predict what will happen if you add a chemical with an unknown biological effect to a substance.   The purpose is _to increase_ (increase) the profit.   Not until   I will not begin until 8.   I will wait for you until 8.           Many other new techniques that enable more research to be done in the test tube to see if chemicals produce harmful biological effects are now available.