When someone asks me "Are you free tomorrow?" How to answer if I wanna say I have some other plan
When someone asks me "Are you free tomorrow?"

How to answer if I wanna say I have some other schedule during that period, so I can't make it.

For example, "I've got some thing to do at that time" ? In Chinese, we usually say 我明天有事。What is the most native way of saying this in English?

Question

When someone asks me "Are you free tomorrow?" How to answer if I wanna say I have some other plan
When someone asks me "Are you free tomorrow?"

How to answer if I wanna say I have some other schedule during that period, so I can't make it.

For example, "I've got some thing to do at that time" ?  In Chinese, we usually say 我明天有事。What is the most native way of saying this in English?

Answer

Hello Loraine
You can simply answer 'I'm sorry I can't make it as I already have plans'
or 'I'm sorry I can't make it but maybe next time I can go with you?'

Hope this helps
Best wishes 
Catherine

Answer

I'm sorry I'm meeting ...
I can't I'm going shopping/visiting my parents/working - or any other reason

I can't I'm busy.

Answer

you can say : 
I would love to come , but unfortunately i should be some where on that time

show(pretend) that you really wanted  to go + but + make a reason

Good Luck
^_^

Answer

Usually， u might know what the person invite you for. For example, a dinner , a party or other activities. What I would say is I really want to join you， but i am afraid I have an appointment（my schedule is quite tiny.）.