13. Let's sing a duet.
来个二重唱吧。
还能这样说：
Let's sing in duet.
Let's sing together.
14. What's your karaoke specialty?
你唱卡拉OK有什么拿手的歌吗?
还能这样说：
What's your best song?
Which songs do you sing the best?
应用解析：
special court 特别法庭;
a special train 专车，临时列车;
special to 对……特别的;
make a special study of 专修，专攻
15. I dare not to sing in front of people.
我不敢在大家面前唱歌。
还能这样说：
I dare not to sing publicly.
I have no courage to sing in public.
应用解析：
out front 在观众席中;
a front for sth. 非法或秘密活动的隐蔽物;
front-page 头版新闻;
front runner 最有可能成功或胜利的人，领先者
16. I can't keep up with the new songs.
我跟不上新歌的速度。
还能这样说：
I can't keep track of the new music.
I can't learn the new songs fast enough.
应用解析：
keep up with the Joneses 赶时髦，与他人攀比;
keep time 合拍子;及时;
keep watch 留意，注意，守望;
for keeps 永远地，永久地;
keep after 紧紧追赶;
keep away 使离开，避开
17. It was the most beautiful song I had ever heard.
那歌声是我所听过的最优美的歌曲。
还能这样说：
I had never heard a more beautiful song than this one.
Among all the songs which I had heard, this one was the best.