Mrs. Smith locked both the front and the back doors before she went to bed ________ that a thief might steal into the house.

1. A.
   so
2. B.
   for fear
3. C.
   unless
4. D.
   in case

Mrs. Smith locked both the front and the back doors before she went to bed ________ that a thief might steal into the house.

A. so　　　　　　　　　　 B. for fear　　　　　　 C. unless　　　　　　   D. in case

A. so　　　　　　　　　　 B. for fear　　　　　　 C. unless　　　　　　   D. in case

Mrs. Smith locked both the front and the back doors before she went to bed ________ that a thief might steal into the house.

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