–I think it’s going to be a big problem.

--Yes, it could be.

--I wonder ________ we can do about it.

A. if           B. how                C. what                D. that

---I think it’s going to be a big problem.
---Yes, it could be.
---I wonder ______ we can do about it.

1. A.
   if
2. B.
   how
3. C.
   what
4. D.
   that

--- I think it's going to be a big problem.

--- Yes, it could be.

--- I wonder          we can do about it.

A. if                        B. how

C. what                     D. that

---- I think it’s going to be a big problem.

---- Yes, it could be.

---- I wonder _________ we can do.

　 A. if　　　　 　　　　　　 B. how　　 C. what　　　　　 　　 D. that

—I think it's going to be a big problem.

—Yes, it could be.

—I wonder ________ we can do about it.

A. if　　　　　　　　　　    B. how　　　　　　　　　　    C. what　　　　　　　　　　    D. that

—Yes, it could be.

—I wonder ________ we can do about it.

A. if　　　　　　　　　　    B. how　　　　　　　　　　    C. what　　　　　　　　　　    D. that

—Yes, it could be.

—I wonder ______ we can do about it.

A. if　　   　　　　　　　　　　　　　　　　　　　　　　　　    B. how

C. what　　  　　　　　　　　　　　　　　　　　　　　　　　　　　   D. that

I think it's going to be a big problem.

Yes, it could be.

I wonder ________ we can do about it.

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