1.but的用法.but主要用于表示转折,意为“但是”：It was a sunny but not very warm day.那一天天气晴朗,却不太暖和.He drives not carefully but slowly.他开车不是很小心,而是开得很慢.【注】不要按汉语意思将“虽然…但是…”直译为although…but…：误：Though we are poor,but we are happy.(去掉though或but中任一个) 2.yet的用法.与but一样,yet也主要用于转折,意为“但是”“而”：I have failed,yet I shall try again.我失败了,但我还要尝试.【注】有时可与并列连词and或but连用,构成习语and yet和but yet,且两者大致同义(均相当于表转折的but)：She drove very fast to the airport,but (或yet,and yet,but yet) she missed the plane.她开快车去机场,可还是误了飞机.应该是yet的语气更强吧.希望可以帮到你,