I
• Use of animals for bioassay antedated ( or preceded , or predated ) use of microorganisms.
• The first appearance of living organisms was preceded by the gradual development of a complex chemical environment.
• The dust and gas that came before the protostars ...
• The study of diffraction by crystals will be preceded by treatments of the classification of crystals.
II
• For singlet states a superscript 1 is prefixed to the letter designation of the state.