The elements of all business letters are the following: the heading, the date, the inside address, the salutation, the body, the signature, and the complimentary close. Therefore, the one that is not part of the elements of all business letters is the references.
So much is at stake in writing a conclusion. This is, after all, your last chance to persuade your readers to your point of view, to impress yourself upon them as a writer and thinker. And the impression you create in your conclusion will shape the impression that stays with your readers after they've finished the essay.
The participle in this sentence is "sweating". It's a participle of the verb " to sweat" and it's a present participle: which we know because it ends with an -ing (past participles end with "-ed).
