This is a great question as it shows the importance of using the appropriate preposition in particular situations.
To stand up for somebody or something means to defend or fight for the other person or thing.
On the other hand, to stand up to somebody or something means to confront or defend oneself against the other person or thing.
Usually, when children are growing up they are taught to stand up for their classmates if he/she is being bullied. Children are also taught to stand up to bullies, they should learn to defend themselves against bullies and defend their friends too.
Here are some more examples of the two phrases being used:
- During the meeting, the manager had to stand up for one of her employees as another manager from a different department was putting all the blame on her employee rather than recognizing his own mistakes. The manager defended her employee and made sure all the blame wasn’t put on him.
- The new waitress needs to stand up to her boss as it is obvious that he is taking advantage of her by asking her to work overtime and not giving her share of the tips. She needs to be assertive and tell her boss this is unacceptable.
- The young protestors are standing up for freedom of speech by joining the protest against the plan to increase college fees for all new and current students studying at colleges and universities.
