Complete the following statements with proper words or expressio

Complete the following statements with proper words or expressions according to the course book. “Bad-mouth” used as a verb can take the past tense marker -ed, e.g. He bad-mouthed me. This example shows a compound tends to play a single ( )role in a sentence.
【正确答案】：GRAMMATICAL
【题目解析】：用作动词的“抨击”可以用过去时标记ed，例如他说我坏话。这个例子表明复合词在句子中往往只起语法作用。