Pencils, papers, protractors, etc., are needed for the project.<br/>(Can the comma be omitted after 'etc.' here?)<br/><br/>Pencils, papers, protractors, and so on, are needed for the project.<br/>(Can the comma be omitted after 'and so on' here?)<br/><br/>Pencils, papers, protractors, and so forth, are needed for the project.<br/>(Can the comma be omitted after 'and so forth' here?)<br/><br/>John, Joe, et al., will attend the symposium.<br/>( Can the comma be omitted after 'et al.'?)<br/><br/>She loves to read non-fiction (e.g., reference books and how-to books).<br/>---Can the comma be omitted after 'e.g.'?<br/><br/>He had one obvious flaw (i.e., his laziness).<br/>---Can the comma be omitted after 'i.e.'?<br/><br/>Thanks.