试题题干
Complete the following statements with proper words or expressions according to the course book.
In the words prewar, bloody, impossible, pre-, -y, im- are called 
affixes.
参考答案
试题解析
在单词prewar（战前的）、bloody（血腥的）和impossible（不可能的）中，pre-，-y和im-是派生词缀，派生词缀是指必须和其他词素结合才能构词的词缀。