In fact, it's easier to understand how to use these words if you think of them as having OPPOSITE meanings. Note that in all these examples, 'NOT ...yet' means that a certain situation is still true. He's still at school = He hasn't left school yet. I'm still reading this book = I haven't finished this book yet. We're still waiting for the bus = The bus hasn't arrived yet. Does that help?

I hope it'll help you ‘Yet’ is used to talk about something which is expected to happen. It means ‘at any time up to now’. It is used in questions and negatives. Have you finished your homework yet? The speaker expects that the homework will be finished. I haven’t finished it yet. I’ll do it after dinner. ‘Yet’ usually comes at the end of the sentence. Still ‘Still’ is used to talk about something that hasn’t finished – especially when we expected it to finish earlier. I’ve been waiting for over an hour and the bus still hasn’t come. You promised to give me that report yesterday and you still haven’t finished it. ‘Still’ usually comes in ‘mid-position’ Still is often used with other tenses as well as the present perfect. I’ve still got all those letters you sent me. Are you still working in the bookshop?

This will be difficult to explain and understand. I apologize. Imagine you are flying from California to Tokyo. Now read this conversation: Son: Are we in Tokyo yet? Mom: No, we're still flying over the Pacific. You are correct that both 'still' and 'yet' refer to 'at this moment'. However, 'still' implies that the condition has not changed. In my example, the airplane has been flying over the Pacific for several hours, so they are 'still flying'. 'yet', on the other hand, implies a future change in condition that has not happened. In my example, they have not arrived in Tokyo, so they are not 'in Tokyo yet'.