人体每个细胞的最外层都是细胞膜 Each cell in your body is surrounded by a cell _____, 这是一层由脂质和蛋白质构成的柔软厚膜 a thick flexible layer made of fats and _____, 它包围并保护细胞内容物 that surrounds and protects the inner _____.
【简答题】6 ( ) 1 The doctor worked___ five hours___ a rest. A. for; with B. on; without C. about; having D. for; without ( ) 2 I worked on the problem ____ a long time and I worked it out____myself____ last. A...
【简答题】根据课文,在下面的选项中选择适当内容填空。(只填序号) 1. What made the author happy when she helped out in the kitchen? made her happy when she helped out in the kitchen. 2. Why would the author put Fred Hasbrook’s order in wi...