There have been quite a few Macmillan Dictionary searches lately for the phrase toing and froing. The spelling of this causes problems for native- and non-native speakers alike, because it feels odd to put –ing after ‘o’, unless the sound you’re trying to create is ‘oi’ (as in the onomatopoeia ‘boing‘). Often people spell it ‘to-ing and fro-ing‘ to make the distinction clear, yet we have no trouble understanding I’m going now, and feel no desire to hyphenate it. So where to and fro are being used as verbs, like go, there’s no need for hyphens, and as odd as it may look toing and froing is perfectly acceptable.
