congratulations与congratulation有什么区别？

congratulations为口头用语，表示祝贺了。congratulation意为表扬，是书面语。

congratulation作不可数时意为“祝贺”,用于一般句中,例如：He gave a speech of congratulation for the winner.He gave sincere congratulation to him.等
congratulation作可数时只用复数形式,即congratulations,其用法有两种：

1. 表示“贺词”,如：offer sb's congratulations on his success。

2. 用作感叹词,如：Congratulations!Congratulations to you!Congratulations on winning the prize!等。