【简答题】请用for或since填空 1. We've lived here _____ 1980. 2. So you've lived here _____ about 30 years. 3. Miss Lin has taught us English _______ we came to this school. 4. I'm looking after Tom today. He's been ...
【单选题】He has never watched such an important match , _____ he?
【单选题】He has just arrived, but he talks as if he ___ all about that.
【多选题】白菜分为四个变种散叶变种、半结球变种、花心变种、结球变种,其中结球变种又分为三个生态型( )。
【简答题】制造硅酸盐水泥的主要原料是()和 ( )。
【简答题】水稻常规种子原种生产单株选择的时期为: 期进行初选, 期逐株复选, 后室内决选。