Without grammar, you can't say much; but without vocabulary, you can't say anything. Vocabulary is the foundation of successful language learning. ESL/EFL learners need to be familiar with a great many words if they want to read, write, listen, or speak with ease. In addition to the sheer number of words and phrases students need to learn, what makes vocabulary acquisition so tricky is that one "pass" is never enough. In order to really "know"...