皮皮学，免费搜题
登录
搜题
【判断题】
蓄电池正接线柱刻有“正”号。 ( )A.
正确
B.
错误
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】两个弯矩图的叠加不是指图形的简单拼合，而是指两图对应的（）叠加。
【单选题】He had promised to come and help us, and ___.
A.
so did he
B.
so he did
C.
so had he
D.
so he had
【单选题】—Don't worry. He'll come and help you. — he doesn't come? [ ]
A.
What
B.
Why
C.
What if
D.
How if
【单选题】— I've asked only one person to come and help us-Sam. — _____ he doesn't come? [ ]
A.
How about
B.
What about
C.
If only
D.
What if