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Small sailboats can easily turn over in the water ________.

A. if not managed carefully                 B. if are not managed carefully

C. unless not managed carefully             D. unless are not managed carefully

Small sailboats can easily turn over in the water ________.

A. if not managed carefully                                 B. if are not managed carefully

C. unless not managed carefully                           D. unless are not managed carefully

 Small sailboats can easily turn over in the water ________.

A. if not managed carefully                                B. if are not managed carefully

C. unless not managed carefully                         D. unless are not managed carefully

Small sailboats can easily turn over in the water ______ they are not managed carefully.

A.though   B.before   C.until   D.if

Small sailboats can easily turn over in the water ______ they are not managed carefully.

   A. though  B. before C. until   D. if

  Small sailboats can easily turn over in the water ______ they are not managed carefully.

   A. though  B. before C. until   D. if

 Small sailboats can easily turn over in the water ______ they are not managed carefully.

   A. though     B. before        C. until         D. if

Small sailboats can easily turn over in the water ______ they are not managed carefully.

A. though             B. before   C. until    D. if

Small sailboats can easily turn over in the water ______ they are not managed carefully.

A. though　　　　 B. before　　　　　　　 C. until　 　　　　　　 D. if