Complex sentence: An electron's position in space is not determined, but its probability of being at a particular place is given by the value of its wavefunction squared,\\ psi ^ 2, at that point.
Split into simpler sentences: An electron's position in space is not determined, but its probability of being at a particular place is. It is given by the square of the value of its wavefunction,\\ psi ^ 2, at that point.