Most frames _______ cast iron, weld steel, composition, or concrete.
· are made from
· are made up of
· was produced by
· was consist of
出自:佳木斯大学语言治疗学

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