[翻译题,4分] Not only is this problem very important, but it is a difficult problem to be solved at once.
出自:河南城建学院大学英语(四)

完成拼图验证

按住下方滑块,将拼图拖到缺口处后松开。

拼图背景,将小拼图拖到缺口处
向右拖动滑块