Being single and ready to mingle can be tough, hence the growing prevalence of fast and convenient online dating. The problem with online dating sites is that they try to match suitable partners using mathematical formulas. But the real magic is in your first impression, and the following examples show what a striking opener can do for you. Traditionally, pick-up lines are seen as ineffective and juvenile—and in any other context, they would be. But on Tinder, the rules are different.