Question

    For hundreds of years the madder plant was our only source of yellow dye. The dye was extracted from the roots of the plant and sold all over the world．The great plantations in Southern France were devoted to the cultivation of the madder plant until 1869．In that year German scientists discovered that the dye could be produced artificially. A chemical that was extracted from coal tar was their answer. Alizarin, as it is called, was cheaper to produce, easier to use and more permanent (永久的) in coloring. The dyers of cloth turned to this new product, and the madder growers of France had to look for new crops to cultivate.

1．Our only source in formers times for yellow dye was ________.

A．chemicals

B．coal tar

C．plant

D．German plantations

2．The chemists discovered ________.

A．a better dye

B．coal tar

C．the madder plant

D．yellow dye

 

Answer 1

答案：C;A
提示：

1.       参看第一句话。 2.       后面说的是一种染料，生产成本更低，更便于使用，颜色保持更长。