Select 与 SelectMany

var query = contact
    .Where(c => c.FirstName.StartsWith("S"))
    .Select(c => new { c.FirstName, c.LastName, c.EmailAddress });

Names[] owners = 
{   new Names { FirstName = "Scott, Chris", Pets = new List<string>{"Yukon", "Fido"}},
    new Names { FirstName = "Jason, Steve", Pets = new List<string>{"Killer", "Fluffy"}},
    new Names { FirstName = "John, Joe", Pets = new List<string>{"Spike", "Tinkerbell"}}
};

IEnumerable<string> query = owners.AsQueryable()
    .SelectMany(owner => owner.Pets);