When assembling puzzle pieces mentally, what should you check to confirm the pieces fit?

To confirm pieces fit, check that the EDGES and ANGLES of adjacent pieces MATCH UP, and that they combine into the target shape WITHOUT GAPS OR OVERLAPS. ASVAB Assembling Objects tests spatial fitting. Each piece's edges must align with its neighbors (a notch in one fits a tab on another); the completed assembly should form a clean, complete shape. Look at distinctive edges/corners to see how pieces connect. Wrong answers often have pieces whose edges don't actually match, leaving gaps or causing overlaps. Matching edges and angles is the key verification step.