mystring1 <- "Other work has shown that, in addition to language-general features such as a decreased speaking rate and an expanded pitch range, clear speech production involves the enhancement of the acoustic-phonetic distance between phonologically contrastive categories 􏰃e.g., Ferguson and Kewley-Port, 2002; Krause and Braida, 2004, Picheny et al, 1986; Smiljanic and Bradlow, 2005, 2007􏰀."
mystring2 <- "Other work has shown that, in addition to language-general features such as a decreased speaking rate and an expanded pitch range, clear speech production involves the enhancement of the acoustic-phonetic distance between phonologically contrastive categories 􏰃e.g., Ferguson and Kewley-Port, 2002; Krause and Braida, 2004, Picheny et al, 1986; Smiljanic and Bradlow, 2005, 2007􏰀. Therefore, reduced sensitivity to any or all of the language-specific acoustic-phonetic dimensions of contrast and clear speech enhancement would yield a diminished clear speech benefit for non-native listeners. This may appear somewhat surprising given that clear speech production was elicited in our studies by instructing the talkers to speak clearly for the sake of listeners with either a hearing impairment or from a different native language background. However, as discussed further in Bradlow and Bent 􏰃2002􏰀, the limits of clear speech as a means of enhancing non-native speech perception likely reflect the “mistuning” that characterizes spoken language communication between native and non-native speakers."
 
rx <- "\\be\\.g\\.,.*?[0-9]{4}[^\\w.]*(?=\\.)"
gsub(x = mystring1, pattern = rx, replacement = "", perl = TRUE)
gsub(x = mystring2, pattern = rx, replacement = "", perl = TRUE)

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