--- You are so lucky.

---What do you mean          that?

A. for                B. in

C. of                D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

---You are so lucky.             

---What do you mean ____that?

A. for　　                      B. in　　          C. of　　              D. by

—You are so lucky.

—What do you mean________ that?

A. for　　　　　　　　　　    B. in　　　　　　　　　　    C. of　　　　　　　　　　    D. by

—What do you mean________ that?

A. for　　　　　　　　　　    B. in　　　　　　　　　　    C. of　　　　　　　　　　    D. by

—You are so lucky!

—What do you mean ________ that?

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