to think that

• to think

to think that

1. Used to express that one is strongly moved or surprised by something.
   • 2011, Anne Marsella, The Baby Of Belleville, →ISBN:

     I was sure to find Honoré at some new trick, standing say, heroically holding onto the back of a chair (oh to think that soon he will walk!) and Charles perhaps playing a pastoral suite on the alpenhorn.

   • 2011, Patrick J. Saddles, Seven Rainbows Over Santa Rosa:

     And to think you hope to get a job in radio? Acting like a fool's fool?

• “to think that” in Longman Dictionary of Contemporary English, Longman.