The Revisers ill-advisedly decided that "all such words, now printed in italics, as are plainly implied in the Hebrew, and necessary in English, be printed in common type."
One of the consequences of this decision is that the very "to be" is not distinguished from the verb "to become", so that the lessons conveyed by the A.V. "was" and "was" in Gen. 1:2; 3 and 4; 9 and 10; 11 and 12, are lost. See the notes on Gen. 1:2.
For the general uses of various types in the English Bible see Ap. 48.