His shy voice trembles over the shimmering tone clusters of his guitar.
Times, Sunday Times
Her voice trembles as she reads out the letters.
Times, Sunday Times
Her voice trembles slightly when she talks about the most important job she'll ever do.
The Sun
His voice trembles when he explains this.
Mail and Guardian
His voice trembles, and he discusses a few of those things, but doesn't go into specifics.
Times, Sunday Times