Ⅰ.单词拼写
根据汉语或首字母提示，写出下列单词。
1．I drop the letter into the mailbox(邮箱)in front of the post office.
2．To achieve my goal，I overcame(克服) a series of unimaginable and challenging difficulties when young.
3．They will concentrate on teaching the basics of reading，writing and arithmetic(算术)．
4．We took the children to the circus yesterday afternoon.
5．The paintings were sold for absurd prices.
6．Having no choice but to let out cries of anger，she felt hopeless．
