Question

请教2道英语选择题 请给出正确答案并讲解 谢谢

1 （），it immediately ran away.
a.Observing her b.On being oberved c.Having been oberved d.On her being oberverd

2 The experts were now fully convinced that the animal ( ) a puma.
a.must be b.should have been c.can only be d.could only have been

Answer 1

1.D On being observed ，一被人看到 on 是介词“一……就……”
“一被看到，它立即就逃跑了”
2.A must 表示非常肯定的推测 “一定是”
“专家们现在充分确信那只动物一定是美洲豹”

Answer 2

每一个选D,
第二个选A.