Robert is said __________ abroad, but I don’t know what country hestudied in.A) to have been studyingB) to studyC) to be studyingD) to be studied
出自:国家开放大学开放英语

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