46. When the verb in a sentence expresses motion, the word indicating the place, person or thing toward which the motion is directed is given the accusative ending. This is also true if the word is the complement of any preposition which does not itself sufficiently indicate motion in a certain direction. (The prepositions al, to, toward, ĝis, as far as, tra, through, express motion in the direction of their complements, and could not well be used except in a sentence whose verb expresses motion. Consequently the accusative is not used after any of these three):
Li iris ĝardenon, he went to the garden ("gardenward").
La viro iros Bostonon, the man will go to Boston ("Bostonward").
Cf. English "he went home," "he went homeward," etc.
Li estis en la ĝardeno, kaj kuris en la domon, he was in the garden and ran into the house.
Ĝi ne estas sur la tablo, ĝi falis sur la plankon, it is not on the table, it fell upon the floor.
Ili falis sub la tablon ĝis la planko, they fell under the table as far as the floor (direction expressed by whole prepositional phrase).
Mi iris tra la domo en mian ĉambron, I went through the house into my room.
THE ARTICLE FOR THE POSSESSIVE ADJECTIVE.
47. In many sentences where the possessor is already sufficiently indicated, English nevertheless uses a possessive adjective, as in "I wash my face," "he shakes his head," but on the other hand omits it entirely with certain words indicating relationship, as in "Brother gave it to me," etc. In both cases Esperanto uses the article instead of the possessive adjective, unless the fact of possession is to be emphasized:
Mi lavas la vizaĝon, I wash my face.
Li skuas la kapon, he shakes his head.
La patro estas alta, Father is tall.
Mi donis ĝin al la patro, I gave it to Father.
APPOSITION.
48. English often uses the preposition "of" between two words where no idea of possession really exists, as "the city of Boston." Since nouns used in apposition refer to the same thing, and are in the same grammatical construction, Esperanto does not use a preposition:
La urbo Bostono estas granda, the city (of) Boston is large.
Mia amiko Johano estas alta, my friend John is tall.
Ĉu vi ne konas min, vian amikon? do you not know me, your friend?