pleasant是please的形容词吗

　　Can I have extension 4332 please?

　　请接4332号分机。

　　Please, sir, can I open a window?

　　老师，请允许我打开一扇窗户好吗？

　　Please could I leave early today?

　　请问，我今天早走一会儿行吗？

　　What's your account number please?

　　请问你的账户号码？