You can wrap a string across multiple lines by setting the text_wrap property of the cell format and by using \n to delimit the lines.

    my $format = $workbook->add_format(text_wrap => 1);
    $worksheet->write(0, 0, "It's\na bum\nwrap", $format);
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See the set_text_wrap() section of the documentation and the text_wrap.pl program in the examples directory of the distro

--
John.