发明人: A Mnich 摘要: Short arc welding system. The present invention refers to a system to control a weld current in a arc welding apparatus for short arc welding comprising a current regulator included in a closed circuit voltage feedback from a power supply to an electric Welding cycle ...
根据第一段中句子Last month I went to Peru with my mom and dad.My mom's company sent her there on business.(上个月我和爸爸妈妈去了秘鲁。我妈妈的公司派她去那里出差。)可知,作者的家人去秘鲁是因为他的母亲不得不在那里工作。故选C。(2)细节理解题。根据第一段中句One ...
Ganquan Canyon(峡谷) in Shaanxi Province has become famous since Chang Bo posted the photos of it online.Chang never expected that his photos would make such a difference to the canyon and the local people's life. The area used to be covered by thick forests and the...