From what I could find, Sirens are asking for help. The song they sing is a cry for help. They are described as acting/singing like a "damsels in distress".
Answer:
<h3>If something changes or is done gradually, it changes or is done in small stages over a long period of time, rather than suddenly. Electricity lines to 30,000 homes were gradually being restored yesterday. Synonyms: steadily, slowly, moderately, progressively More Synonyms of gradually.</h3>
<h2>Hope it helps you.</h2>
To search
Explanation:
To get more information about the instructional manual from the computer
