how to write "@" in inkscape

Type it with the text tool? Pretty much the same as you'd create in with any other program.

Harry, does it answer your question? If so, please consider closing it ;-)

If You are not using English keyboard at the moment, - you would have to switch probably in it and write it in English keyboard layout (because I expect that in German version shortkeys will not function the same way, as the usual Czech shortkeys combination for "@" does not function in Czech version). The letter @ is above "2" (i.e. with shift) in upper row in english keyboard.

Clarification for native english language users: some native language keyboards simply does not offer "@" as a valid keystroke. To produce it, you would have to enter some particular shortkey combination. As far as I know, to produce "@" I can use combination "Alt + Ctrl +V" or "Alt + 6 + 4".
They are working "in any other program" (to cite c's advise) but they do not work in my Inkscape.

This applies for almost all the other symbols in the upper row of the keyboard.

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