Construct the longest coherent sentence you can such that the nth word is n letters long.

Such sentences are also called "rhopalic."

I
do
not
know
where
family
doctors
acquired
illegibly
perplexing
handwriting;
nevertheless,
extraordinary
pharmaceutical
intellectuality,
counterbalancing
indecipherability,
transcendentalizes
intercommunications'
incomprehensibleness.

From "Time" magazine, January 10, 1977:

O
to
see
Man's
stern
poetic
thought
publicly
expanding
recklessly
imaginative
mathematical
inventiveness,
openmindedness
unconditionally
superfecundating
nonantagonistical,
hypersophisticated,
interdenominational
interpenetrabilities.

If you add the condition that the letters in each word must be in
inverse alphabetic order, you have:

A
zo
fed
upon
solid
toffee
zyxomma.