IM or IN, and EM or EN.

The prefix in is from the Latin, and that of en from the French and Greek. In generally signifies situation, and en mostly expresses action. Hence, perhaps, in strictness, inclose will signify “to close in,” and enclose, “to make close.” So, to inquire will be “to seek in, or to search in,” and enquire, to “make search.” Immigrate, “to pass into;” emigrate, “to go out of.” But this distinction is not attended to by writers, and is, indeed, too refined for general practice.

Before the letters b and p, en becomes em, as in embattle, empower; and in before some letters becomes ig, il, im, or ir, as in ignoble, illegal, improper, irresolute.

We give a list of those generally spelt with im or in; leaving it to be inferred that the rest are more usual with em or en.

IN and UN.

In, as a prefix, also marks negation: it is probable that it came from the Romans. Un, as a prefix, is synonymous with in: it is of Saxon origin, and generally joined to words from a northern source; while in is oftener applied to those of Latin derivation.

ISE and IZE.

The variation in the terminations ise and ize is due to the different derivations of words,—ize characterizing words from the Greek and Latin, and ise from the French. The rule, however, is not inflexible. The following words are commonly spelled with the s.