\definefont [TestC] [name:texgyreherositalic*default at 12pt]
\definefont [TestD] [name:texgyreherosbolditalic*default at 14pt]
\starttextframed[frame=off]{%
{\TestA The quick}
{\TestB brown fox}
{\TestC jumps over}
{\TestD the lazy dog}\stoptext}
</context>