单词拼写（共10小题；每小题1分，满分10分）
Because the temperature dropped a________（突然） , the south of China suffered a heavy snow.
Please come to my home to play cards whenever it is______________ (方便) for you.
Books should be c___________ by subjects.
Don’t h_____________ to turn to me whenever you are in trouble.
The doctor said that the patient might be _________________(不舒服) after the operation.
The ancients were ________________(错误) in their belief that the earth was flat.
R_____________ of the colour of his skin, every man has right to live where he wants to.
It is not polite to i_________ when someone is talking.
I can’t ____________(假设) anything in this case.
The explorers had to eat unripe fruits to prevent____________(饥饿).