题干
My grandparents were very tried ,but of them wanted to take a break．
A：none
B：neither
C：both
D：all
答案(点此获取答案解析）
B
和
充人恒容密闭容器中，恒温下发生反应： H2(g)+Br2(g)
2HBr(g) ⊿H <0,平衡时