The disadvantages include the songs may not be the ones you desire to learn and the instruction is more general without any way of knowing where you are in your musical journey.

缺点包括歌曲未必是你的愿望，学习和教学更一般没有任何办法知道你在哪里在你的音乐之旅。

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The Ryan outline by design does not include specifics other than a general instruction to the Ways and Means Committee to overhaul the corporate tax code and simplify the seven individual brackets into two tiers with a top rate of 25%.

WSJ: Review & Outlook: A Ryan Reboot