舞厅: dance hall, ballroom...
长江: Yangtze River, or Chang Jiang...
义务: duty, obligation, volunteer (work etc)...
暑假: summer vacation...
…分之…: fractional number...
奏效: to show results, effective...
不足: insufficient, lacking, deficiency, not enough, inadequate, not worth, cannot, should not...
拔: to pull up, to pull out, to draw out by suction, to select, to pick, to stand out (above level), to surpass, to seize...
的确: really, indeed...
香味: fragrance, bouquet, sweet smell...
