$\begin{array}{1 1} \text{For every positive real number x there exist a number x+1 which is not positive.} \\\text{ For no positive real number x there exist a number x+1 which is not positive.} \\\text{For every positive real number x there exist a number x+1 which is not negative.} \\ \text{For all negative real number x there exist a number x+1 which is positive.} \end{array} $