関連ワード:  how long does it take to learn german from b1 to b2    b1 to b2 german how long    how long does it take to learn german b1    how to go from b1 to b2 german    how long does it take to learn german b2    how long does it take to get to b1 in german  
結果 : how long does it take to learn german from b1 to b2