1.   Clearly, their new fourth would have to be someone who was more than a prodigious musician with a supple voice.

2.   Three of the computers had no password set, while the fourth had an easy-to-guess, default password.

3.   Three of the four displayed patently feminine external genitals, while the fourth had ambiguous genitals.

4.   Among Estonians, every fourth had such a connection, the board said.

5.   Three of four Indian tribes in Kansas operate casinos on their reservations, while the fourth has one nearby.