I don’t remember how many years ago ________ people began to grow crops.

   A. it was when           B. it was that          C. was it when          D. was it that

.

I don't remember how many years ago ______ people began to grow crops.

A. it was when           B. it was that     C. was it when      D. was it that

I don’t remember how many years ago ______ people began to grow crops.

   A. it was when                                        B. it was that           

  C. was it when                                         D. was it that

I don't remember how many years ago ______ people began to grow crops.

A. it was when              B. it was that         C. was it when         D. was it that

I don’t remember how many years ago ________ people began to grow crops.

A. it was when　　　　　　  B. was it that　　　　 C. it was that　　　　 D. was it when

A. it was when　　　　　　  B. was it that　　　　 C. it was that　　　　 D. was it when

I don’t remember how many years ago ______ people began to grow crops.

A．it was when                B．it was that           C．was it when           D．was it that

I don’t remember how many years ago ________ people began to grow crops．

1. A.
   it was when
2. B.
   was it that
3. C.
   it was that
4. D.
   was it when

I don't remember how many years ago ________ people began to grow crops.

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