I think that four of the lines are in fact the same as the cells that you should have hightlighted but including all cells end to end in each case rather than just the hightlighted ones. The other two form the object that they apply to - the last five words of the extra words say where these two should be drawn.
I'm with voulezvous here, I'm afraid. Unless you're saying that the 6 lines are, in fact, only three lines; considered to be six lines if you count that six lines meet at a point in the middle?
So now, I guess, you're saying that the lines have to be drawn through the conic sections that I've already highlighted?
If that's true, what's the point of highlighting them? (that's rhetorical) I mean, if I've already identified what we're looking for, why do I have to show it again a different way?
I agree that is doesn't seem totally satisfactory but fail to see how else it could be. Just drawing the lines using the words as guides would have done fine I would have thought, at least that would have been a fair representation, whereas perhaps just highlighting the words wouldn't really in all cases. (In fact I wouldn't be surprised to hear that the requirement to draw the four lines was added after the puzzle had been reviewed as it was deemed that just highlighting the words wasn't actually quite true.)