2. 外语
  3. They are sweating all over. They ______ in the field.

They are sweating all over. They ______ in the field.

admin2013-12-13  55
问题 They are sweating all over. They ______ in the field.
选项 A、may be
B、must have been working
C、could be
D、must having been working
答案B
解析 情态动词用法题。情态动词可和一个动词的完成进行式构成谓语，表示“想必一直在，应当一直在”等意思。本句must表示肯定推测，同时根据句意，劳动一直在进行，故B项must have been working正确。
转载请注明原文地址:https://kaotiyun.com/show/Q1FK777K
0

专业英语四级

相关试题推荐
随机试题
最新回复(0)