第1个回答 2012-08-13
The chair is broken. I need to fix it. The chair needs to be fixed. 在最后那句被动句中,need to 后边只能接动词原形,因为 “to 不定式”后边是固定的动词原形。即便need to 后边接被动语态,也要求用原形的be,这里是无法改成be的其他形式的。和need to的效果相同的还有can, must, should等,后边都只能接动词原形。如:The chair should be fixed.
如果在简单句中,没有need to,can,must,should这类的动词,be是可以随着时态和主语数格的改变而改变的。如:The chair was fixed just now.
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