1.intentionally == on purpose
do something intentionally[on purpose]
2.by mistake/ by accident 意外地 偶然地 错误地
3.How has your day been today.
4.What I meant is I wish I had paid more attention to my suitcase.
5.Oh my! I would like to give you an apology.
6.I will keep that in mind.
7.You just saved my day.
8.I can't thank you enough. No worries/No problem, I'm happy to help.