let myArray = [{"child": ["one", "two", "three", "four"]},
{"child": ["five", "six", "seven", "eight"]}];
for(let i = 0; i < myArray.length; i++){
let childArray = myArray[i].child;
for(let j = 0; j < childArray.length; j++){
console.log(childArray[j]);
}
}/* Outputs:onetwothreefourfivesixseveneight*/