1 . Be quiet — let me c________ on my homework. (根据首字母提示单词拼写)

2 . John could no longer c__________ on his studies with all that noise going on. (根据首字母单词拼写)

3 . My English teacher is always inspiring us to c_________energy on our studies. (根据首字母单词拼写)

4 . With the noise going on, I found it hard to c________ on my work. (根据首字母单词拼写)

5 . Feeling anxious, I fail to c_______ on the exam paper. (根据首字母单词拼写)

7 . Mike c______ on his homework, not knowing what was happening outside the window. (根据首字母单词拼写)

8 . There were so many people talking that I couldn’t c______ on the music. (根据首字母单词拼写)

9 . C________ your efforts on learning English, and you will master the language. (根据首字母单词拼写)

10 . It was very hard for me to c____ on my homework with my deskmate making all the noise. (根据首字母单词拼写)