What is the exact meaning of 着 and how can I use it in a sentence?
Good question! You get on something small, yet complex. Allow me to put an list here, and get back to it later:
Have seen, saw something
Fall into sleep.
I want to add two more sentences to show the contrast cases.
(1) 哎，你踩着我的脚呢！踩着(zhe) means being standing on something. It is happening right now.
(2) 哎，你踩着我的脚了！踩着(zháo) means a fact that indeed happened. It may be in the past or at present.
Please see the following example too.