1. Ceilingandsealing.Ceiling “the overhead surface of a room” is an instance of the <i>-before- <e> except after <c>. Ceiling comes from the Latin word caelum, which meant “sky” and is the source of our word celestial “pertaining to the sky.” Notice that ceiling and celestial both have <ce>.
Sealing analyzes to seal+ing. Seal originally meant a mark, often a wax impression, that guaranteed something as genuine. Seal is a simplification of the Latin noun sigillum, which in turn came from signum “a distinguishing mark or sign.” Thus, seal is related to many, many words that all contain <s>, including sign, signature, signal, design, insignia, and so on.
2. Consciousandconscience. Conscious and conscience are not quite homophones, but they are close enough in sound that it can be easy to confuse one with the other. The adjective conscious means “aware, either of one's surrounding or of one's own existence.” The noun conscience refers to that inner sense of what is right or wrong and the sense of guilt and concern we can get when we know that we have done something wrong. Conscious analyzes to com + n + sci + ous and contains the adjective-making suffix -ous. Conscience analyzes to com + n + sci + ence and contains the noun-making suffix -ence.
Conscience is related to conscientious: A conscientious person usually has a strong conscience. And in conscientious the stress is on the syllable with the <e>, so you can hear the [e] sound. Remember the link between conscience and conscientious, and you can remember the <e> in the -ence suffix in conscience. So the [s] at the end of the suffix -ence in conscience is spelled <c> with a silent final <e> to mark it as soft; the [s] at the end of the suffix -ous in conscious is spelled <s>.
3. Presenceandpresents. Presence and presents are like a number of other pairs such as patience and patients, and residence and residents. Presence (pre + sence) is a singular noun that means the state or action of being at a place, the opposite of absence. Presents (pre + sent + s) is a plural noun that means “gifts”; it can also be used as a verb, as in “He presents the awards every year.” Usually when a <t> comes between [n] and [s], the <t> does not get pronounced. That is why words like scents,cents, and sense are homophones. A similar set of homophones are the adjective intense and the plural noun intents, which occasionally get confused when people who mean “intents and purposes” write “intense and purposes.”
About all you can do is remember that presents, patients, residents, and intents are plural nouns with the -s plural suffix.
4. In each of the following sentences cross out the incorrect word and write the correct one into the blank:
(ceiling, sealing). They are sealing the packages now.
(patience, patients) The nurse told the doctor there were still three patients in the waiting room.
(conscious, conscience) He was not conscious of the man behind him.
(presence, presents) She received many presents for Christmas.
(residence, residents) Their residence is just down the street.
(ceiling, sealing) The ceiling of his room is so low that Merv has to duck his head when he goes in there.
(conscious, conscience) After the party at their house, he seemed like he had a guilty conscience.
(patience, patients) Chess is a game that requires a lot of concentration and patience.
(residence, residents) The residents of the condominium complained to the manager.
(conscious, conscience) Her conscious wouldn't let her tell that kind of lie.
Item 2. This distinction is complicated by the singular noun present “now” and the rare law term presents meaning “the present writings or text,” as in “Know all men by these presents.”
Homophones and near homophones are examined in Lessons 35-36 and 47 of Book 7. For more on homophones see Harold C. Whitford, A Dictionary of American Homophones and Homographs (NY: Teachers College Press, 1966).