The Apollo spacecraft therefore had three primary components: a command module (CM) with a cabin for the three astronauts, and the only part that would return to Earth; a service module (SM) to provide the command module with propulsion, electrical power, oxygen, and water; and a two-stage lunar module (LM), which comprised a descent stage for landing on the Moon and an ascent stage to return the astronauts to lunar orbit.
ðɪ ɐpˈɑːloʊ spˈeɪskɹæft ðˈɛɹfoːɹ hæd θɹˈiː pɹˈaɪmɚɹi kəmpˈoʊnənts: ɐ kəmˈænd mˈɑːdʒuːl sˌiːˈɛm wɪð ɐ kˈæbɪn fɚðə θɹˈiː ˈæstɹənˌɔːts, ænd ðɪ ˈoʊnli pˈɑːɹt ðæt wʊd ɹᵻtˈɜːn tʊ ˈɜːθ; ɐ sˈɜːvɪs mˈɑːdʒuːl ˌɛsˈɛm tə pɹəvˈaɪd ðə kəmˈænd mˈɑːdʒuːl wɪð pɹəpˈʌlʃən, ᵻlˈɛktɹɪkəl pˈaʊɚ, ˈɑːksɪdʒən, ænd wˈɔːɾɚ; ænd ɐ tˈuːstˈeɪdʒ lˈuːnɚ mˈɑːdʒuːl ˌɛlˈɛm, wˌɪtʃ kəmpɹˈaɪzd ɐ dᵻsˈɛnt stˈeɪdʒ fɔːɹ lˈændɪŋ ɔnðə mˈuːn ænd ɐn ɐsˈɛnt stˈeɪdʒ tə ɹᵻtˈɜːn ðɪ ˈæstɹənˌɔːts tə lˈuːnɚɹ ˈɔːɹbɪt.