Many e___ have been done to find out medicine to deal with such adisease

Many e___ have been done to find out medicine to deal with such adisease
He has gone to work n______.There's nothing wrong with him.
E-mail English is c____ to tpye quickly and save time when people chat online.
People in China and English behave d_______ at the dinner table.
我们的课是以一首中文歌开始的.
Oue class __________ a Chinese song.