分析從句中的句子成分,主、謂、賓齊全即為狀語(yǔ),主、謂、賓不全即缺主語(yǔ)或賓語(yǔ),例：
This is the factory that we visited last week.（visit缺賓語(yǔ))
This is the factory where I used to work.（主、謂、賓齊全）