Many have heard it, but nobody has ever seen it. It will not speak back until spoken to. What is it? The answer to the riddle is an echo. Echo is the reflection of the sound that when it is released by the speaker, it arrives back to the speaker (now listener) but is delayed.
It is a sentence that contains both an independent clause and one or more subordinate clauses
Ok. What is the question?
Its a street in the central Barcelona? not sure if correct just asumming
