The group of birds were flying in the morning. Coldplay was the winner. The majority of the group were drinking coffee. For next time remember that "were" is used when the subject is in plural e.g. birds, they, we. "Was"is used when the subject is singular e.g. Coldplay, I, she. However special attention need to be given to the usage of a group such a family, team or simply group. In these group cases both "was" (singular) or "were" (plural) can be used. "When the group is being considered as a whole, it can be treated as a single entity: “the group was ready to go on stage.” But when the individuality of its members is being emphasized, “group” is plural: “the group were in disagreement about where to go for dinner.”" http://public.wsu.edu/~brians/errors/group.html Hopefully this helped :)

Typically, it depends on how the speaker/writer is thinking. If you are thinking of the group as a single entity, then "group was". => The group was scheduled to perform... If you are thinking of the group as many individual birds, then "group were". => The group were tried and went to bed.

This is a tricky one, but a common issue to come up. English uses logical number agreement with groups rather than the strict grammatical agreement that many languages use. Usually you use a plural verb with groups if it is clear you are talking about the individuals in it, if they are acting separately. That's the case in your third example. But if you are talking about the group as a whole, then it should be singular. That's probably the case with your second example. But in your first example, you could say either, depending on whether you are emphasising the individual or group behaviour. It could depend on how you define "group of birds". But if you had said "flock of birds", where flocking stresses the way the birds interact with each other and take on a single shape, then I would use singular. Also be aware that usage varies a bit by dialect. So American usage tends to go for singular in some cases where British English tends to prefer plural. It's not absolute either way, it's just a tendency, but you will hear it especially in cases like companies, governments and sports teams.