Question

—Why didn’t Susan come to school? —I don’t know. She____ ill. A．could be B．may have been

—Why didn’t Susan come to school? —I don’t know. She____ ill. A．could be B．may have been C．might D．must have been

Answer 1

B

本题回答语表示的含义是苏珊可能生病了，所以导致的后果是她未能上学，故用情态动词may+完成时态的结构，故本题选B。