Unua Posxta Kurso (Esperanto-English)

I just got the first lesson in Esperanto-USA's Free postal course.

Birdo kaptas insekton. = A bird catches an insect. (Subject-noun verb object-noun).

Esperanto is grammar-coded:
-o = single subject-noun
-on = single object noun
-oj = plural subject-noun
-ojn = plural object-noun
-as = present tense verb
-is = past tense verb
-os = future tense verb

Brido kaptis insekton = The bird caught an insect
Birdoj kaptos insektojn The birds will catch insects.

La = the

La viroj vendis kukojn. = The men sold cakes.
La viro vendis kukon. = The man sold a cake.

Vocabulary:
Nouns
Amiko = friend
Birdo = bird
Filo = son
Fisxo = fish
Frato = brother
Insekto = insect
Instruisto = Instructor
Kafo = coffee
Knabo = child
Kuko = cake
Lakto = milk
Pano = bread
Patro = father
Sukero = sugar
Teo = tea
Viro = man
Verbs
Fari = to do / to make
Forgesi = to forget
Havi = to have
Kapti = to catch
Trinki = to drink
Vendi = to sell
Vidi = to see
Other
Kaj = and
Kun = with
Sen = without
Colors
Flava = yellow
Verda = green
Blua = blue
Blanka = white
Nigra = black
Griza = gray
Bruna = brown

Free word order in Esperanto
(Viro kaptas fisxon = Fisxon kaptas viro = kaptas fisxon viro, etc)

Study Aid Exercise:
The friend will sell milk. = La amiko vendos lakton. (Check)
Mother drinks coffee with milk and sugar. = Patrino trinkas kafon kun lakto kaj sukero. (Check)
The teachers forgot the tea. = La instruistoj forgesis la teon. (Check)
The boys will make the cake. = La knaboj faros la kukon. (Check)
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La knabinoj vidos la instruiston. = The girls see the instructor. (Wrong - The girls will see the instructor)
La instruisto vidis la knabinojn. = The instructor saw the girls. (Check)
La filoj trinkas teon sen lakto. = The sons drink tea without milk. (Check)
La birdoj vidis la insektonjn. = The birds saw the insects. (Check)

I completed and sent in the exercise but will not reproduce it here.

(Esperanto-USA)