Regex capture rest of sentance after last match

Say I have a sentence where I would like to match (and eventually replace but that is not part of the question) certain markers based on what they look like:

The quick brown fox {NUM} jumped over {211NUM} the lazy dog {NUM}. The Quick brown fox {NUM10} jumped over the lazy dog.

I would like to replace the {NUM}, {#NUM} and {NUM#} parts based on logic and the number in the #. And then put it all back together as a single string.

I came up with

(.*?)({NUM}|{\d*NUM}|{NUM\d*})

which will obtain the captures I would like, but I cant seem to figure out how to get the REMAINING part of the sentence after the last match, i.e. jumped over the lazy dog.

I thought maybe adding (.*?) to the end would do it but it does not. Here is what I have working:

https://regex101.com/r/HpIcAa/1

No need to trash garbage collector with split/concating strings. Replace works good, no memory spikes, fast, accept functions as argument too:

public class Program
{
    public static void Main()
    {
        var pattern = @"(?<num>\{((?<n1>\d+)?NUM|NUM(?<n2>\d+))\})";
        var regx = new Regex(pattern, RegexOptions.ExplicitCapture | RegexOptions.Multiline);
        var input =
            @"The quick brown fox {NUM} jumped over {211NUM} the lazy dog {NUM}.  The Quick brown fox {NUM10} jumped over the lazy dog. ";

        var output = regx.Replace(input, ToReplaceMatch);
        Console.WriteLine(output);
    }

    private static string ToReplaceMatch(Match match)
    {
        if (match.Groups["num"].Success)
        {
            var num = int.TryParse(match.Groups["n1"].Value ?? match.Groups["n2"].Value, out var res)
                ? res
                : (int?)null;
            return ToReplaceNum(num);
        }

        return match.Value;
    }

    private static string ToReplaceNum(int? number)
    {
        return "FOOBAR" + (number ?? 0);
    }
}

Output:

The quick brown fox FOOBAR0 jumped over FOOBAR211 the lazy dog FOOBAR0.  The Quick brown fox FOOBAR0 jumped over the lazy dog.

You could try to match only your keywords using this regex pattern: (?<g1>{NUM})|(?<g2>{\d*NUM})|(?<g3>{NUM\d*})

Then using Regex.Replace function to replace keywords based on your logic.

string pattern = @"(?<g1>{NUM})|(?<g2>{\d*NUM})|(?<g3>{NUM\d*})";
string input = "The quick brown fox {NUM} jumped over {211NUM} the lazy dog {NUM}.  The Quick brown fox {NUM10} jumped over the lazy dog. ";
output = Regex.Replace(input, pattern, delegate(Match match)
{
	if (match.Groups["g1"].Success)
    {
       return "{Group 1}";
    }
	if (match.Groups["g2"].Success)
    {
       return "{Group 2}";
    }
	if (match.Groups["g3"].Success)
    {
       return "{Group 3}";
    }
	return match.Value;
});

See demo here