The benefit of group work that is demonstrated in this example is enabling a complex task be broken down to simpler and fewer works. Since each individual had been given fewer task, it leads to increase of productivity while saving the time consumed in finishing the project.
The last answer sets the most formal tone; "Hello! I was very pleased to meet you at the party last week." the rest are very casual.
Character traits are a valued aspects of a person's behavior.
Answer:
Winston Smith is still technically married to Katherine