单词拼写。 1. In modern times some ______(青少年) have got into the habit of taking drugs. 2. As the child has never seen a ______(彩虹)before, he was very excited. 3. Don't be _______ (失望的) when you fail for the first time. 4. Instead of _______ (吸烟), do something else. 5.The eruption of a volcano is an ______ (绝对地;完全地) fantastic sight.