Hi Yuening,
In the Mathematica notebook interface, strings are not enclosed in quotes in output cells. If you want to see the quotes use InputForm
data1 = {"title1", "title 2", "title 3"}
(* {title1, title 2, title 3} *) (* No quotes displayed *)
InputForm@data1
(* {"title1", "title 2", "title 3"} *) (* Quotes are displayed *)
WordCloud@StringRiffle@data1
I am not sure what you mean by "does not work". Were you expecting that "title 2" would be treated as a single element rather than "title" and "2"? If you want that, remove the StringRiffle
. But with long titles it is probably not what you want because that was the original question you asked.