9. (单选题) -Oh, thank you. I __________ how to do it.(本题2.0分)
A、 had wondered
B、 would wonder
C、 was wondering
D、 did wonder
出自:东北林业大学-大学英语3

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