Okay, so you're conversing with someone you know is really, really smart (i.e., smarter than you), and suddenly she says a word that you just know is the wrong word. It's close, but you know it's just dead wrong. Are you the type to correct? Or just let it go? What if she's testing you? You don't want her thinking you don't know, do you? Or maybe she just doesn't know, but she's the type who would love to know, and you'd be doing her a favor to point it out.
Meanwhile, here are some words that either you know and it drives you crazy when they're flipped, or you don't know and you wish you did.
historic(al). That is historic which holds an important place in history. Thus Napoleon's return from Elba ("Able was I ere I saw Elba," he palindromed) was a historic event, Neil Armstrong's words as he stepped onto the lunar surface a historic utterance.
All things historic are also historical in the sense that they belong to authentic history, but the great mass of historical figures and events have nothing historic about them: historic = special; historical = actual. It is thus possible to use historical to affirm or deny the truth of a supposed event.
The great meltdown of 1999-2000 is not historical. Had it in fact taken place, the occurrence would have been both historical and historic.
judicial, judicious. It is possible to find a halfhearted sanction in some dictionaries for treating these two words as synonyms, but the inevitable result of doing so is misleading. Common sense enjoins us to make the distinction established by usage between judicial, characteristic of court procedure or of the legal mind, and judicious, characterized by judgment, discernment, or wisdom.
It is clear that judiciously would avert confusion in such a sentence as The problem confronting their owners is where to run them [race horses] judicially in order to preserve their peak competitive condition for the Triple Crown.
compose, comprise. The whole is composed of its parts; the whole comprises its parts. The parts compose the whole and are comprised in it. Comprise, the word that produces most of the trouble, expresses the relationship of the larger to the smaller, not the other way around.
If we think of comprise as meaning take in, we shall escape the pitfall into which even good writers manage to stumble.
The suburbs of large cities also are avoided . . . because their booming populations are comprised mainly of white-collar workers. Not so: the booming populations are composed of white-collar workers, and these workers are comprised in the booming populations.
The denomination is comprised of three sects. On the contrary, it is composed of three sects, and it comprises them. For the new poems which comprise the present volume read: the poems compose the volume (or the volume comprises the poems). The politicians comprise (compose) most of that shrill group. (The group comprises the politicians.)
The whole comprises the parts.
The parts are comprised of the whole.
The whole is composed of the parts.
The parts compose the whole.