--nk-leading-tight

Lines set close read as one thought. Lines set open read as a list. The leading decides before the words do.

--nk-leading-normal

Lines set close read as one thought. Lines set open read as a list. The leading decides before the words do.

--nk-leading-relaxed

Lines set close read as one thought. Lines set open read as a list. The leading decides before the words do.