London, Nov 11: The apostrophe has emerged as the punctuation mark, which causes most problems for Britons, according to a new survey.
The survey of nearly 2,000 UK adults revealed that almost half were unable to use the apostrophe properly.
The most common mistake was not knowing how to punctuate a possessive plural.
The test, set by the SpinVox speech technology company, revealed that 46 percent of those who sat it thought that, in the context set, "people''s choice" was wrong - whereas it is correct.
The adults were also asked which mistake most annoyed good punctuators.