{underscore <textwheel1|block>}, {asterisk <textwheel1|block>}, {one two <textwheel1|block>}, {three four <textwheel1|block>}, {a <textwheel1|block>}, {b <textwheel1|block>}

{{strong <textwheel1|block>}} and {em <textwheel1|block>} and {{strong <textwheel1|block>}} and {em <textwheel1|block>}

{line <textwheel1|block>
line <textwheel1|block>
line <textwheel1|block>}


an empty emphasis {} {{}} is not an emphasis

{mixed {{double and <textwheel1|block>} single asterisk <textwheel1|block>}} spans <textwheel1|block>