It is ______ he often fails in exams ______ makes his parents worried about him.
A large sum of money has been raised the poorly-educated children in the mountainous areas.
David gave us a vivid of his trip to Mount Huangshan after his return.
When you keep your promise, no matter how much effort (努力) it takes, you will be .
The happy of children playing in the garden disappeared, and it was quiet again.
—What shall I do if I meet a word that I don’t know?—If you can’t guess its meaning, you can the dictionary.