题目

34.I can’t quite remember________my daughter started dancing.    A. how did        B. it was when      C. when it was that       D. where was 答案：C下列变化既不需要加入还原剂，又不需要加氧化剂就能够实现的是A .F2→F-        B. Cl2→Cl-           C .Mg→Mg2+        D. Na→Na+