Complete the following statements with proper words or expressions according to the course book.The semantic ( ) of idioms is reflected in the illogical relationship between the literal meaning of each word and the meaning of the idiom, as is shown in rain cats and dogs.
【正确答案】：UNITY
【题目解析】：The semantic unity of idioms is reflected in the illogical relationship between the literal meaning of each word and the meaning of the idiom, as is shown in. 习语的语义整体性也反映在习语中每个词的字面意义和习语真正意义之间的非逻辑关系上，如rain cats and dogs（倾盆大雨）所示。
