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这不是一套让你死记硬背的课程。四节课从认识键盘开始，依次理解音程、三和弦与三和弦转位，把每个概念立即放回琴键上练习。This is not a course built around rote memorization. Across four lessons, you will move from keyboard orientation to intervals, triads and triad inversions, bringing every idea straight back to the keys.
四节横向 PDF 课件已经整理完成：认识键盘、音程、三和弦、三和弦转位。可在线打开或下载复习；此前发布的旧版练习课件仍保留在课件页底部。Four landscape lesson PDFs are ready: keyboard orientation, intervals, triads and triad inversions. Open them online or download them for review; the earlier practice booklet remains archived at the bottom of the materials page.
从黑键“2 + 3”的排列找到 C，认识七个音名和键盘循环，再理解升号、降号与黑键的关系。专门面向第一次接触键盘的学习者。Use the black-key groups of two and three to find C, learn the seven note names and keyboard pattern, then understand how sharps and flats relate to the black keys. Designed for first-time keyboard learners.
学习半音与全音、小二度与大二度、小三度与大三度、纯四度与纯五度。数音名字母判断几度，数相邻琴键步数判断半音；这一课不进入和弦。Learn half and whole steps, minor and major seconds and thirds, and perfect fourths and fifths. Count note letters for the interval number and adjacent key steps for semitones; chords are left for the next lesson.
认识大三和弦、小三和弦、增三和弦与减三和弦的基本构成，并学习常见和弦标记，看到标记就知道应该弹哪一种三和弦。Learn how major, minor, augmented and diminished triads are built, together with their common chord symbols, so each symbol points clearly to the triad you need to play.
理解原位、第一转位和第二转位，先判断最低音，再用最简单的键盘示范感受同一个三和弦如何改变排列与位置。Understand root position, first inversion and second inversion by identifying the lowest note, then use simple keyboard examples to hear and feel how the same triad changes shape and position.