皮皮学，免费搜题
登录
搜题
【单选题】
下面不是产生X线所必须的条件A.
产生高压
B.
灯丝加热并发射电子
C.
阳极必须旋转
D.
控制装置
拍照语音搜题，微信中搜索"皮皮学"使用
参考答案：
参考解析：
知识点：
皮皮学刷刷变学霸
举一反三
【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?
A.
hasn't
B.
has
C.
is
D.
isn't
【单选题】He has just arrived, but he talks as if he ___ all about that.
A.
know
B.
knows
C.
known
D.
Knew
【简答题】听对话和问题，选择正确答案。 ( )1. A. He has a sore throat. B. He has a toothache. C. He has a fever. ( )2. A. His left leg hurt. B. He had sore eyes. C. He had the flu. ( )3. A. More than three hours a...
【简答题】制造硅酸盐水泥的主要原料是()和 ( )。
相关题目：