If you are looking for alternative textbooks or resources, there are a range of options available, including:
Searching for the "with key" version is highly beneficial for independent learners. Having the solutions at your fingertips allows for immediate feedback, which is crucial for internalizing correct grammar rules. How to Use the Key Properly If you are looking for alternative textbooks or
: Never look at the key before finishing an exercise. If you are looking for alternative textbooks or