# If you'd like to omit non-matching lines from the result; add ';d' to the end of the expression.
sed -E 's/(?:Mo|Tu|We|Th|Fr|Sa|Su)+\s*[\d]{2}:[\d]{2}A?P?M\s*-\s*[\d]{2}:[\d]{2}A?P?M//gm;t' <<< "MoWe 04:30PM - 05:50PM
Fr 12:00PM - 01:20PM
fooo
"
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for SED, please visit: https://www.gnu.org/software/sed/manual/html_node/The-_0022s_0022-Command.html