Winston Churchill was a stutterer. To overcome it, he would pre-empt every argument and practice all possible replies weeks ahead of time!
Stuttering is a speech impediment that is often worsened by stress. This sometimes makes it difficult for a person who stutters to confidently speak in public. Winston Churchill, who was a stutterer himself, was determined to find a solution for this problem.
Churchill was the leader of the Conservative Party in Britain and was known for his sharp wit. Churchill is well known and fondly remembered for his witty quotes like "there are two things that are more difficult than making an after-dinner speech: climbing a wall which is leaning toward you and kissing a girl who is leaning away from you."
He always seemed to have an answer to anything that was put to him and could express it fluently. But this did not come without a lot of extra effort.
He prepared his remarks weeks in advance and memorized them. He studied issues and prepared a speech. He would then write a response for every possible objection that could come from it, and learned them all by heart so that he would not stutter when responding. This made him sound more knowledgeable than other leaders.
He practiced his speeches, along with speech-building phrases like "the Spanish ships I cannot see since they are not in sight."