§ 10. Compound words
Compound words consist of two or more roots: «теплоход», «ледокол». The roots are often joined by the connecting vowel «о» or «е»: «тепл-о-ход», «земл-е-трясение»; sometimes without a vowel: «двухэтажный». Compound-abbreviated words are formed in several ways: from the initial sounds of words, read as one word («ГЭС», «АЭС»); from the names of letters, read letter by letter («МГУ», said «эм-гэ-у»); from syllables of words or from the beginning of one word plus a whole word («спортзал» — «спортивный зал», «турбаза» — «туристическая база»). The gender of an abbreviation is often decided by its head word: «ГЭС» is feminine («станция»), «АЭС» is feminine («электростанция»), «МГУ» is masculine («университет»). «Пол-» (“half”) is written together with a word that begins with a consonant: «полчаса»; before a vowel, «л» or a capital letter a hyphen is used: «пол-яблока», «пол-литра», «пол-Намангана».
“Abbreviation code”. The teacher writes an abbreviation («АЭС», «МГУ», «спортзал»); groups expand it and give its gender.