“American food is tasteless and greasy because Americans use too many canned, frozen, and prepackaged food and because everything is fried in oil or butter” is a good topic sentence.

解析: 【解析题】12.DNA的三级结构是指 【解析题】 川南宜宾哪一个丹霞与天然竹林林海融为一体,衍生了较为Read More