1. The problem asks to identify triangles similar to \(\triangle HFE\).\n\n2. Similar triangles have the same shape but may differ in size. This means their corresponding angles are equal and their corresponding sides are proportional.\n\n3. Given \(\triangle HFE\) with right angles at \(E\) and \(H\), we look for triangles sharing these angle properties.\n\n4. Since \(FE\) is perpendicular to \(HG\), \(\angle HFE = 90^\circ\) and \(\angle HEF = 90^\circ\) in the smaller triangles formed.\n\n5. The triangles \(\triangle HFE\) and \(\triangle \square\square\) (the square) share the same angles, so \(\triangle HFE \sim \triangle \square\square\).\n\n6. Similarly, \(\triangle HFE\) and \(\triangle \blacksquare\) (the rectangle) also share the same angle measures, so \(\triangle HFE \sim \triangle \blacksquare\).\n\nFinal answer: \(\triangle HFE \sim \triangle \square\square\) and \(\triangle HFE \sim \triangle \blacksquare\).