Please choose the correct ending to complete the given sentence: Sports and Fitness: [header] How to throw a slider [title] Place your index and middle fingers. [step] Grip the baseball with your index and middle fingers placed tightly together across an outer seam of the ball located at the horseshoe or u-shape seam. For right-handers, place your middle finger across the right half of the seam.

Ending1: For left-handers, place your ring and pinky fingers over the seams at the center seam. [substeps] For most slider pitches, you'll first alternate grip up and down. Ending2: Left-handers should do the opposite: place your middle finger across the left half of the seam. This should position your fingers towards the outside of the ball (off-center). Ending3: A lefty can place the middle finger on the left half of the seam, while lefties should place the middle fingers on the inside seam. [title] Position your second and third finger on the opposite seam. Ending4: For left-handers, place your middle finger across the seam for the momentum to deliver a two-handed slider. [substeps] Slide your middle finger across the horseshoe seam.

Answer format: ending1/ending2/ending3/ending4