问题补充：
单选题Whatagreatweightthemotherfelt____hermindthemomentshefoundherlostson!A.turned offB.brought intoC.set freeD.taken off
答案：
D解析本题考查动词短语。句意为：当她找到失踪的儿子时，顿时感觉心中如释重负。Take off 有“去除(=remove)”的含义，即felt a great weight taken off her mind,其主动式为： take a great weight off her mind. ,其他三项不符合题意。故选D.
