用方框中所给单词或短语完成下列句子。 Thank-you note, successful, crowded, small, talk, unsuccessful, elevator 1. There are so many people here! This party is really too ______ ,isn't it? 2. I'm writing a ______ to my sister for the birthday present she sent me. 3. Sometimes I don't know what to say when I'm trying to make a ______ in a conversation. 4. This ______ is really slow, isn't it? 5. Both______ people must ask questions to have a small talk.