1. The next day, November 29, Roosevelt seemed alert as ever.
    第二天，11月29日，罗斯福看上去和平日一样的活跃。

2. These children showed a reasonable level of happiness and were very alert during periods of study.
    这些孩子显示了相当不错的快乐感，在学习过程中反应也很敏捷。

3. 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.

4. 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.

5. When these made a sound, they had to make a note of what they were doing and assess how happy and alert they felt.
    当发出声响时，他们就要记下当时孩子们正在干什么，并评估孩子们从中所感受到的快乐和反应的敏捷程度。