Many of the rhythms which follow have snare or bass drum beats on the "e’s" and/or "a’s". When playing an eighth note hi-hat pattern, these "e’s" and/or "a’s" fall half way between the corresponding hi-hat beats (see example).
The hi-hat (right hand) has a tendency toward playing with the "e’s" and/or "a’s", and so to remedy this problem, snare or bass drum beats falling on the "e’s" and/or "a’s" can be synchronized with the upstrokes (see example).