lˈɛt ˈɛs biː ɐ pˈɔɪnt ʌv ˈɛs ænd lˈɛt ˌɛlˈɛs biː ðə kˌɔːɹɪspˈɑːndɪŋ lˈaɪn ɔnðə kjˈuːbɪk ˈɛf. lˈɛt sˌiːˈɛs biː ðə dᵻvˈaɪzɚɹ ˌɔn ˈɛs pˈæɹəmˌɛtɹaɪzɪŋ lˈaɪnz ðæt kˈʌt ðə lˈaɪn ˌɛlˈɛs.
Let s be a point of S and let Ls be the corresponding line on the cubic F. Let Cs be the divisor on S parametrizing lines that cut the line Ls.