1.What is smog and its harm
2.The cause of smog
3.Some solutions
I watched a speech by Jake Ma https://www.youtube.com/watch?v=CZfp0ZUsBdM
He was keeping eye contact with the audience from left to right. not just one single group in the middle. Even though he is not a native English speaker, his voice is full of confidence and changes his tone depending on the situation. He did not move a lot but his gesture makes his audience easy to follow his point.