You can download free quiz books here https://docs.mylang.org/
Some examples
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1563%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1681%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1615%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1618%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1625%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1583%26viewonline%3D1
https://docs.google.com/viewer?url=https%3A%2F%2Fdocs.mylang.org%2Findex.php%3Fdo%3Ddownload%26id%3D1577%26viewonline%3D1