def pres_text(trial):
    """
    input:  current presentation trial # (int)
    output: presentation instruction text (string) for given presentation trial
    """
    pres1 = ' Now we will begin the main experiment! ' \
                    'Again you will see cue icons, followed by a series of image pairs and letters (and a fixation cross).' \
                    '\n\n Remember to: ' \
                    '\n\n        Keep your eyes staring at the cross' \
                    '\n        Shift your attention to the SAME cued side and part for EACH pair' \
                    '\n        Immeditaely press 1 ("x") or 3 ("o") when you see the letter ' \
                    '\n\n Do you have questions? Ask them now! ' \
                    '\n Otherwise, position your hand over the 1 and 3 buttons, clear your mind, and press any key to begin. '

    pres2 = ' Feel free to take a moment to rest, if you like! ' \
                    ' When you\'re ready, we will do another round with a cue, followed by image pairs and letters.' \
                    ' \n\n Remember to: ' \
                    '\n Keep your eyes staring at the cross' \
                    '\n Shift your attention to the SAME cued side and part for EACH pair' \
                    '\n Immeditaely press 1 ("x") or 3 ("o") when you see the letter ' \
                    '\n\n Press any key to begin. '

    instructions = [pres1, pres2]

    if trial >= 1:
        num = 1
    else:
        num = 0

    return(instructions[num])