Some people believe that if you ________ a mirror, you ________ have seven years of bad luck.
一些人相信如果打碎一面镜子的话，就会有七年的厄运。if…，…will…条件句句型，故B项句 型错误；根据原句可知时态应为一般现在时，故选A而不选C和D。