Tries to prevent 10,000 mistakes and then measures your ability by how many mistakes you make.
Conversation is important, and it's now easy to test. Every conversation book in the galaxy is now obsolete.
Except this one.
Is all conversations, conversation tests, and you find and fix your own mistakes.
Language learning is not rocket science. Every child on earth does it without grammar.
Language learning is human nature: Conversation.
This is Conversation-Based Learning.
Grammar-based English is like the diet industry. It seems logical that it would work, but the success rate is 2%.