This incredible and nasty Gotcha surfaced in the Lessons, where I (mi'e nitcion) claimed that lenu in lenu tivni la SEsamis.strit. [cu] se tcika li ze, cu was optional. Trapped by Nora:
No. This parses as:
({} KEI) {se tcika}] KU> <li>} VAU).
This shows that the nu...kei is treated like a brivla and is the first part of a tanru, with the second part of the tanru being "se tcika"; so it's a nu...kei type of se tcika as the 1st sumti. The "cu" is necessary, therefore!
lenu punji le sovda be lo'e cipnrkuku kukuku zvati le zdani be lo'e drata cipni. Take one of the "ku"s out and the parse changes.
(Edit: Changed 'lenu that' to 'that lenu' so it made sense in the sentence.)