so tired与too tired
so tired: 好累 The boy was so tired that he fell asleep immediately. 这男孩太累了，马上就睡着了。 I couldn't concentrate, presumably because I was so tired. 我的精神集中不起来，大概是太累了吧。 too tired: 太累了 She had to admit that she was too tired. 她不得不承认她太累了。 I'm too tired...