Watch How Do You Know (2010) HD Full Movie Free on SolarMovie. Watch How Do You Know (2010) online free. After being cut from the U.S.A. softball team and feeling a bit past her prime, Lisa finds herself e...After being cut from the U.S.A. softball team and feeling a bit past her prime, Lisa finds herself evaluating her life and in the middle of a love triangle, as a corporate guy in crisis competes with her current, baseball-playing beau.