practical_coroutines_4.kt

runBlocking {
    val scope = CoroutineScope(Dispatchers.IO)
    val j = scope.launch {
        println("Inside parent job")
        delay(50)
        val p = launch {
            println("Inside child job")
            delay(500)
            println("Ending of child job")
        }
        p.join()
        println("Ending of parent job")
    }
    j.join()
}

Output: 
Inside parent job
Inside child job
Ending of child job
Ending of parent job