1. On the exterior, he was cool, calm and collected but on the interior, stress was killing him.
    表面上，他显得沉着、冷静和泰然自若，但他内心深处的压力使他筋疲力尽。

2. I like animals, too, especially leopards.They are always so calm and alert.
    我也喜欢动物, 优其是豹, 它们永远都是这么镇静和机警.

3. I like animals, too, especially leopards.They are always so calm and alert, just like kungfu masters.
    我也喜欢动物, 优其是豹, 它们永远都是这么镇静和机警, 就象功夫大师.

4. It does involve a willingness to stay with each other in times of pain, struggle, and despair, as well as in times of calm and enjoyment.
    这种承诺意味着不论在恬适欢乐时，还是在艰难困苦、失意绝望时，都愿意厮守相伴。