Online Technical Writing: Spelling Problems

This section covers the most common conventions—or rules—concerning grammar, usage, and punctuation. It also discusses how to handle numbers, abbreviations, and symbols in technical writing. The discussion of the various problems or errors in this section uses the terminology explained in the section on sentence structure and patterns. If any terms, such as object complement or antecedent, are unfamiliar to you, go to that section.

If you have problems with spelling, they may only be a few specific areas that you can overcome once you identify them and practice a bit. The sections in the following review some of the most common areas of spelling problems.


For some writers, their main spelling problem is similar-sounding words, for example, principle and principal or affect and effect. Here is a list of these commonly confused homonyms, with examples of their correct use.

    accept, except
    The construction form accepted the offer to build the bridge.
    Everything has been finished except for the paint job.
    advice, advise
    The construction firm ignored the engineer's advice.
    The engineer advised the firm to use single suspension walkways.
    affect, effect
    The effect of the increased oil prices has been devastating on
    our economy.
    The increased oil prices have affected our economy drastically.
    cite, site, sight
    The consulting engineer cited a paragraph from the building code.
    At the construction site, the workers carefully erected the
    The collapse of the walkways was a terrible sight.
    complement, compliment
    The programmer has received many compliments on her new system.
    The colors that have been selected for the room do not
    complement each other.
    counsel, council, consul
    She was appointed consul to the embassy in Beirut.
    There was lenthy debate on the tax proposal at city council last
    He counselled her to get a degree in technical communications.
    its, it's
    It's time to go home; it's getting late.
    The car has lost one of its headlights.
    lose, loose
    Your car loses power when it is out of tune.
    I have some loose change in my pocket.
    Don't let Mamie get loose!
    personal, personnel
    They plan to take out a personal loan to build the deck.
    Send your application to the personnel office.
    The CEO wants to have a personal chat with all this company's
    principal, principle
    The principal component of the solar panel is the collector.
    Explain to me the principle of convection.
    stationary, stationery
    Use company stationery for company business purposes only.
    The derrick may not remain stationary during the gale-force
    than, then
    My utility bill higher this month than it was last month.
    The hurricane reached the Texas coast; then it plunged right
    into the heart of Houston.
    their, there, they're
    Their calculus course is much harder than ours.
    Over there on the table is your calculus book.
    They're not taking calculus this semester.
    to, too, two
    Are they going to pave the street today?
    It is still too rainy to pave the street.
    Two hours ago, the sky was clear.
    whose, who's
    Whose technical writing book is this?
    There is the woman whose technical report won top honors.
    Do you know who's in charge around here?
    He's a man who's not afraid of criticism.
    your, you're
    Your technical writing book is on the table.
    You're going to have review Part 1 before writing that report.

Doubled internal consonants

Many words double internal consonants while others do not: for example, recommend, accommodate, and committee. Try memorizing these in contrasting pairs (recommend and accommodate, for example).

Internal syllables or letters

Many words have short, practically unpronounced internal syllables that are easily omitted or misspelled: for example, athletics, category, disastrous, optimistic, privilege, and desperate. Perhaps the only way to learn these is to repeat them several times, emphasizing the internal syllable: for example, ben-EH-fi-cial, bound-AH-ries, cat-EH-go-ry.

Words with endings such as -ance and -able

Another source of spelling difficulties is words with similar-sounding endings: extravagant, occurrence, compatible, irresistible, and performance.

Words ending in -sede, -ceed, and -cede

Still another group of confusingly spelled words is that group ending in -sede, -ceed, and -cede: for example, precede, proceed, exceed, supersede. Again, the best thing to do is memorize them or look them up.

The groups of words discussed above are by no means all of the possibilities. You may have trouble with words ending in -or and -er or those ending in -ary, -ery, and -ory. Make your own lists of such word groups that give you problems in spelling.

The silent -e rule

When words end in a silent -e (for example, write), you drop the -e when adding a suffix (write + ing = writing), except when the suffix begins with a consonant (excite + ment = excitement).

The rule for -ie and -ei

Use i before e except after c in words in which the sound is a long e (as in "feet") in words such as piece, receive, and fiend. There are exceptions to this rule: leisure, either, weird, and seize.

Doubling consonants

When you add a suffix to a word ending in a consonant, make sure you know whether to double the final consonant: drag becomes dragged, but equip becomes equipment.

Words ending in -y

When adding a suffix to a word ending in -y, make sure you know whether to change the y to i: enjoy becomes enjoys, but try becomes tries.

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