我有两个函数,我希望第二个函数在第一个函数完成后运行它的动画

您可以使用animationend活动.

function firstRun(){
    rightBox.style.animation = "TextEffectMadeWithCSS 10s";
    rightBox.addEventListener('animationend', secondRun); //once it's finished.
}

function secondRun(){
    rightBox.style.animation = "TextEffectMadeWithCSS 10s";
    rightBox.removeEventListener('animationend', secondRun);
    //remove the listener so this doesn't loop.
}