Was ________ at the air battle on June 8,1994,________ was led by Caplain Johnson ________ Peter lost his life?

1. A.
   it,when,that
2. B.
   that,that,who
3. C.
   it,which,that
4. D.
   it,which,when

Was __ at the air battle on June 8,1994, ____ was led by Captain Johnson ___ Peter lost his life?

 A. it; when; that        B. that; that; who      C. it; which; that      D. it; which; when

It was 8 o’clock at night ________ he had an terrible traffic accident．

1. A.
   before
2. B.
   since
3. C.
   until
4. D.
   when

Was it 8 o’clock ________ you heard someone ________ at the door?

1. A.
   when; knocking
2. B.
   when; knock
3. C.
   that; knocking
4. D.
   that; knock