Question

written lenguages that use symbols for sound instead of symbols for object and ideas are easier to use because

Answer 1

Having symbols for sounds instead of objects is more flexible - it means that you can make up a new word for a new object (such as a laptop, something unheard of a generation ago) without having to make up a new symbol. Plus it allows writers to make up new words, such as Lewis Carroll who made up words like runcible. If he'd had to make up a symbol for that word, no-one would have known how to say it.