一道选择题
___theme parks have___is that they combine normal tourism with larning.
a . what in common
b. that in common
c. where in common as
d. what in common with
答案是A 为什么啊?请详解
参考答案:what可引导名词性从句，具体到这里引导的是主语从句。have...in common固定表达法，意思是有...的共同点。
B，C语法不对，语意也不通顺，D项的with多余。