More examples of real concessions and refutations: Right here
Again, counterarguments, refutations, concessions... these are not required. But they can be a very effective persuasive technique in the right moment. Read through these at your leisure.
More examples of conclusions: Right here
There are so many great ways to conclude a persuasive essay. Check these out - there are some really great ideas in here. You can use emotive language, answer the "So what?" question and appeal to a universal idea, do a call-to-action...
More examples of introductions: Right here
So many ways to make a great intro. We've gone over many of them in class. Notes for the Best Introduction Ideas Ever