In making such models, skills as well as thorough knowledge of plant structure are ______.
A. called on B. called up C. called for D. called in
出自:统招专升本-----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