That line works for me in bash. You may want to look before that line in the script. 99% of the time I get that error, it's from missing a quotation mark somewhere before the line it's telling me the error is in.
E.g., if I put an echo with only one quote mark on the line before, I get the same error as you.
# cat test
#! /bin/sh
echo "
tput cup 18 4; echo "Accept? (y)es or (n)o: "
# ./test
./test: line 3: syntax error near unexpected token `('
./test: line 3: `tput cup 18 4; echo "Accept? (y)es or (n)o: "'
#