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Q. Is it acceptable to divide the name of a state or city at the end of a line, as in a column of a three-column page, when not dividing the name would leave a lot of white on the line?
A. We do it. Most publishers have typesetting guidelines that tell whether such breaks are permissible. Almost anything that’s set in three columns will benefit from generous hyphenation, which helps avoid the ugliness you describe, especially if the columns are fully justified. If the right margin is ragged, you can get away with fewer hyphens.