Question: Can you recommend a language learning tool that focuses on vocabulary building and reinforcement for intermediate learners?

Retention is a good option, with an AI-powered service geared for intermediate and advanced learners. It offers exercises that reinforce and expand what you already know, with AI-curated study materials and a vocabulary collection that learns what you know. It works with multiple languages and can be tailored to your level, so it's good for keeping your language skills fresh over time.

Another good option is Lingvist, which uses AI to personalize learning and focuses on the vocabulary you're most likely to need in real-world situations. It offers courses on the web and mobile devices and uses spaced repetition to help you retain what you've learned, so it's good for learners who want to review and practice vocabulary at their own pace.

If you prefer more interactive and immersive learning, Write2Learn is a good option. It taps into authoritative dictionaries like Collins and Cambridge and offers interactive dialogues, sentence diagrams and AI-powered text analysis to help you learn words in context. It's particularly good for English language learners who want to learn words in real-world situations.

Last, Quizlet offers a full study suite with tools like spaced repetition, flashcards and personalized tutoring. It accommodates multiple question types and offers study modes to help you learn and retain information. It's not specifically geared for vocabulary, but spaced repetition and interactive features make it a good option for language learning.