选D
先把这句话转为陈述句,即:
This flat is ___ you once lived in.
很显然,be动词is后缺少表语,所以用the one指代the flat,后面的you once lived in为定语从句,引导词为which/ that,但在这里中心词the one在定语从句中做宾语,所以引导词可省略.
选D
先把这句话转为陈述句,即:
This flat is ___ you once lived in.
很显然,be动词is后缺少表语,所以用the one指代the flat,后面的you once lived in为定语从句,引导词为which/ that,但在这里中心词the one在定语从句中做宾语,所以引导词可省略.