The document discusses effective strategies for teaching vocabulary. It defines vocabulary as all the words in a language. Key principles for teaching vocabulary include introducing words in context, focusing on useful words, teaching learning strategies, repetition, and spacing practice. Knowing a word involves understanding its meaning, form, and use. When introducing a word, teachers should address some combination of its meaning, pronunciation, spelling, grammatical functions, and other aspects. Good vocabulary activities focus on useful words, teach a learning concept, involve active engagement, and avoid interference from unknown related words.