GRAMMAR LESSON

"i.e."
-- or --
"e.g."

Although commonly confused and misused in colloquial English, e.g. (exempli gratia) and i.e. (id est), both from Latin, are not equivalents.




Exempli gratia, which means "for example", is used before giving examples of something:

I have lots of favorite colors, e.g., blue, green, and hot pink.

Id est, which means "that is" or "in other words", is used before clarifying the meaning of something when elaborating, specifying, or explaining rather than when giving examples:

I can't decide on one favorite color, i.e., I have many favorite colors.

A common mnemonic for English speakers is:

i.e. = "in effect" and e.g. = "example given"

REFERENCES

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