A chord is a combination of three or more notes.
（和弦是三个或更多音的组合）
Chords are built off of a single note, called the root.
（和弦是从一个音建立起来的，这个音叫作根音）
In this lesson, we will discuss triads. They are created with a root, third, and fifth.
（本课中，我们来学习三和弦。三和弦由根音、三音、五音构成）
A major triad (or major chord) is built with a major third and a perfect fifth from the root.
（大三和弦是由从根音开始的大三度加上从根音开始的纯五度构成的）
Let's write a C major triad. First, write the root (C) on the staff.
（我们来写一个C的大三和弦。首先在五线谱上写上根音：C）
Next, write the generic third and generic fifth from the root.
（然后写它之上的三度和五度）
We now need to determine the specific intervals on the keyboard.
（我们现在在钢琴键盘上定义它们的具体音程）
Since we need a major third, let's count up four half steps from the root.
（我们需要一个大三度，从根音开始向上数四个半音）
For the perfect fifth, go back to the root and count up seven half steps.
（接下来我们需要一个纯五度，那么再从根音向上数七个半音）
Since the chord contains no black keys, we do not need to write any accidentals on the staff.
（这个和弦不包含任何黑键，我们不需要在五线谱上写变音记号）
A C major triad is C—E—G.
（C的大三和弦的组成是C-E-G） | 
Next, let's try an E-flat major triad.
（接下来我们试一下降E的大三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Now, switch to the keyboard. Start at the E-flat and count up four half steps for the major third.
（现在来看钢琴键盘。从降E开始然后向上数四个半音得到大三度）
Go back to the root and count up seven half steps for the perfect fifth.
（再从根音开始向上数七个半音得到纯五度）
Finally, write any needed accidentals. In addition to the already-written E-flat, we need a flat next to the B.
（最后在五线谱上写上需要的变音记号，除了降E以外还需要降B）
An E-flat major triad is E-flat—G—B-flat.
（降E的大三和弦是降E-G-降B） |
Next, let's try a B major triad.
（接下来我们写B的大三和弦）
Write the generic third and fifth on the staff.
（先在乐谱上写从根音开始的三度和五度）
Count the major third (4 half steps) and perfect fifth (7 half steps).
（再在键盘上从降E开始然后向上数四个半音得到大三度，七个半音得到纯五度）
Finally, write the needed accidentals on the staff. We need two sharps: one for the D and one for the F.
（最后在五线谱上写上需要的变音记号，我们需要两个升号：升D和升F）
A B major triad is B—D-sharp—F-sharp.
（B的大三和弦是B-升D-升F） |
Next, we will discuss the minor triad. It is created with a minor third and a perfect fifth from the root.
（接下来我们来看小三和弦，它是以小三度和纯五度构成的）
Let's build a C minor triad.
（我们来写一个小三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Now, switch to the keyboard. Start at the C and count up three half steps for the minor third.
（现在看钢琴键盘。从C开始然后向上数三个半音得到小三度）
Go back to the root and count up seven half steps for the perfect fifth.
（再从根音开始向上数七个半音得到纯五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
A C minor triad is C—E-flat—G.
（C的小三和弦是C-降E-G） |
Let's build an E-flat minor triad.
（我们来写一个降E的小三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Next, count the minor third (3 half steps) and perfect fifth (half steps).
（再在钢琴键盘上，从降E开始然后向上数三个半音得到小三度，七个半音得到纯五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
An E-flat minor triad is E-flat—G-flat—B-flat.
（降E的小三和弦是降E-降G-降B） |
Let's build a B minor triad.
（我们来写一个B的小三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Next, count the minor third (3 half steps) and perfect fifth (7 half steps).
（接下来，在钢琴键盘上从B开始然后向上数三个半音得到小三度，向上数七个半音得到纯五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
A B minor triad is B—D—F-sharp.
（B的小三和弦是B-D-升F） |
The augmented triad is built with a major third and an augmented fifth.
（增和弦是大三度和增五度构成的）
Let's build a C augmented triad.
（我们来写一个C的增三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Now, switch to the keyboard. Start at the C and count up four half steps for the major third.
（现在来看钢琴键盘。从C开始然后向上数四个半音得到大三度）
Go back to the root and count up eight half steps for the augmented fifth.
（再从根音开始向上数八个半音得到增五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
A C augmented triad is C—E—G-sharp.
（C的增三和弦是C-E-升G） |
Let's build an E-flat augmented triad.
（我们来写一个降E的增三和弦）
Write the generic third and fifth on the staff.
（在五线谱上各写一个距离根音三度和五度的音）
Next, count the major third (4 half steps) and augmented fifth (8 half steps).
（再在钢琴键盘上从降E开始然后向上数四个半音得到大三度、七个半音得到纯五度）
Finally, write any needed accidentals. In this example, no additional accidentals are needed.
（最后在五线谱上写上需要的变音记号，本例中的和弦不需要变音记号）
An E-flat augmented triad is E-flat—G—B.
（降E的增三和弦是降E-G-B） |
Let's build a B augmented triad.
（我们来写一个B的增三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Next, count the major third (4 half steps) and augmented fifth (8 half steps).
（再在钢琴键盘从B开始然后向上数四个半音得到大三度，七个半音得到纯五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
A B augmented triad is B—D-sharp—F-double-sharp.
（B的增三和弦是B-升D-倍升F） |
The last triad that we will discuss is the diminished triad. It is built with a minor third and a diminished fifth.
（最后我们来学习减三和弦。它是由小三度和减五度构成的）
Let's build a C diminished triad.
（我们来写一个C的减三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Now, switch to the keyboard. Start at the C and count up three half steps for the minor third.
（现在来看钢琴键盘。从C开始然后向上数四个半音得到小三度）
Go back to the root and count up six half steps for the diminished fifth.
（再从根音开始向上数六个半音得到减五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
A C diminished triad is C—E-flat—G-flat.
（C的减三和弦是C-降E-降G） |
Let's build an E-flat diminished triad.
（我们来写一个降E的减三和弦）
Write the generic third and fifth on the staff.
（先在五线谱上各写一个距离根音三度和五度的音）
Next, count the minor third (3 half steps) and diminished fifth (6 half steps).
（然后在钢琴键盘上从降E开始，向上数三个半音得到小三度，六个半音得到减五度）
Finally, write any needed accidentals.
（最后在五线谱上写上需要的变音记号）
An E-flat diminished triad is E-flat—G-flat—B-double-flat.
（降E的减三和弦是降E-降G-倍降B） |
Next, let's build a B diminished triad. Write down the root and generic intervals.
（接下来我们写一个B的减三和弦，先在五线谱上写根音）
Write the generic third and fifth on the staff.
（在五线谱上各写一个距离根音三度和五度的音）
Next, count the minor third (3 half steps) and diminished fifth (6 half steps).
（在钢琴键盘上，从B开始向上数三个半音得到小三度，六个半音得到减五度）
Finally, write any needed accidentals. No accidentals are needed.
（最后在五线谱上写上需要的变音记号，本例中不需要使用变音记号）
A B diminished triad is B—D—F.
（B的减三和弦是B-D-F） |
Use this chart to reference the four types of triads.
（这张表是本科学习的四种三和弦）