The study found songs in 2014 like Stay With Me by Sam Smith, Whispers by Passenger and Unmissable by Gorgon City have a "low happiness" trend. However, tracks from 1984 like Glory Days by Bruce Springsteen, Would I Lie To You? by Eurythmics and Freedom by Wham had a "high happiness" trend. "The public seems to prefer happier songs, even though more and more unhappy songs are being released each year，" the researchers wrote.

　　Apart from the emotional trends, researchers discovered that dances and pop were the most successful styles of music and that there was a "clear downward" trend, with the popularity of rock beginning in the early 2000s. "So it looks like, while the overall mood is becoming less happy, people seem to want to forget it all and dance，" Komarova wrote in an email.

　　It was also found that the "maleness" of songs-the frequency of male singers in popular music-had decreased during the last 30 years. "Successful songs are characterised by a larger percentage of female artists compared to all songs，" they wrote.

　　This discovery appears at a time when the conversation around sex equality in the music industry is at its height, with more male artists and songwriters.

　　【解题导语】　本文是一篇说明文，主要介绍了流行音乐表达的情绪的变化趋势。

　　5．The researchers examined lots of songs to ________.

　　A．find songs for dances and parties

　　B．choose songs for a journal

　　C．release more songs

　　D．know better about songs

　　D　解析：推理判断题。文章第二段介绍了加州大学的研究者们调查了成千上万的歌曲并把它们按情绪分类，紧接着得出歌曲分类的结果，可见他们调查歌曲的目的是想对歌曲有更多的了解，故选D。A、C两项曲解文意；B项无中生有。

　　6．Whose music style tends to bring you more happiness?

　　A．Natalia L. Komarova's.

　　B．Sam Smith's.

　　C．Gorgon City's.

　　D．Bruce Springsteen's.

D　解析：细节理解题。根据第三段中的"However, tracks from 1984 like Glory Days by Bruce Springsteen...had a 'high happiness' trend．"可知D项正确。Natalia L. Komarova为报道的合著者，而非歌手；Sam Smith、Gorgon City所演唱的歌曲有让人开心感降低的趋势，故排除。