House prices keep rising these days. A flat in our city costs ______ now as in 1990.A.as three times muchB.as much three timesC.much as three timesD.three times as much
参考答案：
D解析倍数表达句型。倍数+ as + adj. +as …。房价这些天一直上涨，在我们这座城市买一套房的花费现在是1990年的三倍。
