said to show that you understand why someone has a particular opinion or feels a particular way

"I'm so annoyed with her." "I'll bet." “我实在太烦她了。”“我相信。”

"I was so relieved I didn't have to clean up after the party." "I bet you were." “晚会结束后我不必留下来收拾打扫，这让我大大松了口气。”“我知道你会这样。”