Mara nyingi, tunatumia (indefinite article) 'a' kama tukitaja mtu au kitu tunachokielezea kwa mara ya kwanza na (definite article) 'the' kama tayari kinafahamika kwa wengine tunaowasiliana au ongea nao. Mfano, kama nilikutana na mkazi fulani nisiyemjua Dar es Salaam jana na kama nitataka kuongea habari zake, nitasema 'I met a man/woman dressed in red ni Dar es Salaam yesterday.Maneno "a" pamoja na "the" ni kifungu cha mameno ambayo huwa yanatumika kama utambulisho wa nomino katika lugha ya kiingereza .utofauti wa haya maneno mawili ni:-
"A" hutumika kutambulisha nomino ambayo haina umbo maalum.kwa mfano:- tuchukue nomino ambayo haina umbo maalum kama "maji" basi sentensi itakuwa, "this is a water from indian ocean".hatuwezi kusema "this is the water from indian acean.
"THE" ni kinyume cha "A" ambapo hutumika kwa ajili ya utambulisho wa nomino ambayo ina umbo maalum hapa tutumie kitabu sentensi yetu itakuwa ni, "this is the book".hatuwezi kusema "this is a book
nafikiri nitakuwa kidogo nimetoa darasa kwa ambao walikuwa wakichanganyikiwa juu ya maneno haya mawili.
Halafu baada ya kusema hivyo, nikirudia kumtaja sitasema tena 'a' maana kwa sasa 'audience' yangu inafahamu kwamba ninaongelea mtu niliyekutana naye Dar es Salaam jana, hivyo nitatumia 'the'. Mfano: The man/woman (na siyo 'a') I met yesterday was killed in a road accident. Angalia pia matumizi ya 'a' mbele ya 'road accident' na siyo 'the'. Lakini nikitaka kutumia 'the' nitasema, 'He/she was killed in the road accident as he was crossing Mtakuja Road in 'Wagagagigigogo City'.
Lakini kuna pia majina famous ya mbuga za wanyama, mito au mengineyo ambayo hatutumii 'a' hata kama tukiyataja kwa mara ya kwanza, bali 'the' - mfano, The Serengeti, The East African Rift Valley, The Nile, The Indian Ocean, The Pacific, The Moon, The Sun etc na majina mengine tunaacha kutumia (kuna moot 'the') - mfano, Lake Tanganyika, Lake Victoria, Mount Kilimanjaro, Oldonyo Lengai.