"Many of the images come from the edges of the dataset where there is one or more data channels missing. This produces triangular or zig-zag blocks of blue, yellow, or red. You don't need to mark these as artifacts because we know where the edge of the survey are."
there is one or more -> there ARE one or more
where the edge of the survey are -> where the edgeS of the survey are.
"Many of the images come from the edges of the dataset where there is one or more data channels missing. This produces triangular or zig-zag blocks of blue, yellow, or red. You don't need to mark these as artifacts because we know where the edge of the survey are."
there is one or more -> there ARE one or more where the edge of the survey are -> where the edgeS of the survey are.