第二节 语法填空(共10小题；每小题1. 5分，满分15分)
阅读下面短文，按照句子结构的语法性和上下文连贯的要求，在空格处填入一个适当的词或使用括号中词语的正确形式填空，并将答案填写在答卷标号为3l-40的相应位置上。
Six days of spring rain had created a wild river ___31___ (run) by Nancy Brown’s farm. As she tried to drive her cows to higher ground, she ___32___ (slip) and hit her head on a fallen tree trunk. Nancy was badly hurt and could only walk with great ___33___ (difficult).
