[lojban-beginners] grammar check for my first few sentences

[Alan Post <alanpost+keyword+lojban.420f97@sunflowerriver.org>]

I've begun the process of memorizing vocabulary, and have selected
the first few words from Robin Lee Powell's flashcards[1].  I'm
constructing sentences using these words, and I'd like to know if my
sentences are gramatical.

My first sentence:

.i mi cusku le mlatu do la lojban
(I talk about the cat to you in lojban.)

I'm not sure that saying "le mlatu" in the x2 is proper.  I'm not
sure if the x2 place of cusku permits saying "the cat" or whether I
need a different or additional word.

My second sentence:

.i se lu pa re ci li'u cusku do
("123" you said.)

Are the lu/li'u required here?  Is this the same sentence as "se pa
re ci cusku do" or is that saying "the concept of 123 you speak
about?"  I assume the status of lu/li'u is the same if you replace
"pa re ci" with "coi."

I suppose I might be tripping up on the exact meaning of the x2
"cusku" in both sentences, though I'm also trying to construct
sentences with cmavo in them, as that is what is recommended to
learn many of first.

As a final aside:

In "Direct quotations" in Lojban for Beginners[2], the sample sentence
for lu/li'h has a "cu" in it:

  lu le munje li'u cu cmalu

I would guess that the "cu" is optional, because the terminator li'u
is used.  Is this correct?

Thank you for your help,

-Alan

[1]: http://www.digitalkingdom.org/~rlpowell/hobbies/lojban/index.html
[2]: http://www.tlg.uci.edu/~opoudjis/lojbanbrochure/lessons/less7quote.html