你用不用投影仪？Will you be using an OHP?图像完全对齐时，投影仪的位置就应该固定下来。When the images line up exactly, the projectors should be fixed in place.我们的主人从房里牵出一根延长电线，架起屏幕和投影仪。Our host ran a long extension cord out from the house and set up a...

“投影仪”的英语可以翻译为：[计] projector ...