根据所给首字母或汉语提示完成单词。
The old s                is, "Who laughs last, who laughs best!"
I had a toothache, so I must go to see the               （牙医）.
It's hard to               （选择） the best answer to the question.
He saw some               （老鼠）in the street yesterday.
My brother Jack is more               （外向的）than me.