var multiLine = @"This is a multiline paragraph";
This is a
Multi-line strings that contain double-quotes can also be escaped just as they were on a single line, because they are verbatim strings.
var multilineWithDoubleQuotes = @"I went to a city named ""San Diego"" during summer vacation.";
It should be noted that the spaces/tabulations at the start of lines 2 and 3 here are actually present in the value of the variable; check this question for possible solutions.