阅读下面短文，用括号内所给动词的适当形式填空，必要时可加助动词或情态动词（请将各小题的答案写在短文后相应的横线上）

She has never learned any new words by heart but has a vocabulary of more than 10,000 words．She   1  (begin) to learn English when she was five and a half．And the most surprising thing is that she    2    (pass) CET-4(英语四级考试) before she   3    (graduate) from her primary school．Her name is Liu Yimong, a 13-year-old Junior One student in the High School Affiliated to Renmin University of China(人大附中)．

Liu     4    (ask) to learn English by her mother at the very beginning．Her big success results from her good learning habits．Since long ago, Liu    5   (have) the habit of practicing her English listening in the morning and evening．She usually    6   (listen) to VOA, BBC and New Concept English(新概念英语)．As for her spoken English, she keeps on    7  (practice) it every Friday at the English Corner．Liu said, "It's important     8    (carry) on practicing while learning a foreign language．" Now you     9     (understand) why she     10    (be) so good at English．