下列每个句子均有一个错误，请找出并改正。（注意：每句只有一个错误。）
There are a pen and two books on the desk.
Two third of the people were badly injured during the earthquake.
At last, the Mekong enters into the South China Sea.
Amy is the only one of the girls who come from France.
By the end of last year, we have learnt 3,000 words.
You won’t find difficult to solve the problems.
You can borrow so many books as you want.
Mice ran out of the fields looked for places to hide.
I prefer to watch TV rather than reading a boring book.
I’m eighteen years old and I live in small village.