1. "nationality" -- "national"
2. "spend a whole day to learn" --- "spend a whole day learning"
3. "except" -- "except for"
4. "Then we gathered together for our dinner in their dormitory." 中的”their"指代不明.
5."each one was" --- " all were"
6. "a old friends" --- "an old friend"
7. "was" -- "is"