Statement A, + 可是 + Statement B
可是 (kěshì) is a conjunction meaning "but" or "however," used to introduce a contrasting or unexpected statement. It is slightly softer and more colloquial than 但是 (dànshì). It appears at the beginning of a clause to signal a contrast with what was previously said.
我想去,可是没有时间。
Wǒ xiǎng qù, kěshì méiyǒu shíjiān.
I want to go, but I don't have time.
他说得很好,可是做不到。
Tā shuō de hěn hǎo, kěshì zuò bú dào.
He speaks very well, but he can't do it.
这件衣服很好看,可是太贵了。
Zhè jiàn yīfú hěn hǎokàn, kěshì tài guì le.
This piece of clothing looks great, but it's too expensive.