As is known to all language learners, newly learnt words will soon be forgotten unless used in everyday munication.
A. exactly
B. finally
C. gradually
D. frequently
网友回答
A. exactly
B. finally
C. gradually
(答案→)D. frequently
解析：A. exactly确切地，B. finally最后地，C. gradually逐渐地，D. frequently频繁地，句意：所有语言学习者都知道，新学习的单词很容易忘记，除非在每天的交流中经常被使用。根据句意选D。