—You should have thanked her before she left.
—I meant ________, but when I was leaving I couldn’t find her anywhere.

—You should have thanked her before she left.

—I meant ________, but when I was leaving I couldn’t find her anywhere.

A．to do             B．to               C．doing             D．to have done

—You should have thanked her before she left.
—I meant ________, but when I was leaving I couldn’t find her anywhere.

1. A.
   to do
2. B.
   to
3. C.
   doing
4. D.
   to have done

—You should have thanked her before she left.

—I meant ________, but when I was leaving I couldn’t find her anywhere.

A. to do 　　　　　B. to　 　　　　　　C. doing 　　　　　　　D. to have done