Watch the FOUR! online guitar lesson by Jennifer Batten from 50 Ultra Intervallic Guitar Licks You Must Know
This one is made of diatonic fourth intervals. Diatonic means that it is coming from the major scale (D in this case), so not every 4th will be a perfect 4th. A perfect 4th higher than the note G would be C but C is not in the D major scale. The C would be sharp in a D major scale, therefore a 4th higher than G is C #. i.e., a "sharp 4". Each of the first groups of eight notes uses a similar sequence. When you are playing with a lot of large intervals, using sequences and patterns makes it easier for the listener to grasp. This one ends in a series of bends, the last of which is a large minor third bend.