So, the way we're going to find C Sharp and D Flat on the bass guitar is by finding C and D and finding the note that's in between them. We know that the third string, A open will get us to D and get us to C Sharp, where we really want to go by skipping a note between A and B to get to the second fret. We don't skip a note between B and C, and then we skip a note to get to D. So, the note in between the fourth fret is going to be C Sharp and D Flat. So, if we know that that's true, we can also find the same C Sharp and D Flat by doing the same thing on different strings. C is the fifth fret on the G String and we can find that with the same type of logic. If we know that G is the name of the string when it's open, and we skip one fret we get to A. We skip one fret to get to B. And then we don't skip to get to B and C. We arrive at C at the fifth fret. We skip a note to get to D, so that space in between, which is the sixth fret on the G String, is C Sharp and D Flat. We can also find it at the eleventh fret on the D String, which makes sense because if we know that the twelfth fret is D and we know that by going back one note, we're going to get that same C Sharp, D Flat. And we can also find it on the sixteenth fret of the A String. We can also find it at the ninth fret on the E String. And that's how you play C Sharp and D Flat on the bass guitar.