第一步:初步构思你的introduction,稍稍勾勒出来。Read your main idea. Now, write a complete sentence about your main idea.第二步:扩充你的introduction,记住写它是为了吸引读者注意!Reread your introductory sentenc
The material of choice of a given era is often its defining point; the Stone Age, Bronze Age, and Steel Age are examples of this. Materials science is one of the oldest forms of engineering and applied