I often hear sentences (mis)constructed in this way.
Problem:
There is a singular/plural mismatch.
Explanation:
The phrase “a lot of cats” is singular, even though “cats” is plural, because “a lot” is singular.
The “are” form of the verb “be” is plural.
So there is a mismatch in number between “are” (plural) and “a lot of cats” (singular).
Solutions:
“There is a lot of cats here.”
or
“There are lots of cats here.”
I often hear one of these words spoken with the pronunciation of the other word.
Problem:
The nouns “cache” and “cachet” are not synonyms and should not be pronounced in the same way.
Explanation:
The noun “cache” means a hidden storage space and is pronounced just as “cash” is pronounced. The French verb “cacher” — which means to hide — is the origin of this noun.
The noun “cachet” means an official seal and is pronounced just as “sashay” is pronounced.
The noun “cache” is accurately used in the field of information technology, for example, to refer to a special portion of computer memory, and it’s accurately used in the military to refer to where weapons are hidden by the enemy.
The noun “cachet” is accurately used in the fashion industry, for example, when describing attractive clothing (e.g., “a dress with the cachet of a top designer”).
Speakers most often seem to get into trouble with these two words when they pronounce “cache” in the way that “cachet” should be pronounced.
Solution:
Use “cache” (rhymes with “cash”) when referring to a store of something. Use “cachet” (rhymes with “sashay”) when referring to something that has a recognized endorsement.
I occasionally see “supercede” when the writer means something else.
Problem:
“Supercede” is a misspelled word.
Explanation:
“Supercede” is a misspelling of “supersede” and reflects the combination of the influence of other words (e.g., “intercede”) and an ignorance about the roots of words.
The verb “supersede” literally means to sit upon or above — from “super” (from the Latin “super”: upon or above) and “sede” (from the Latin “sedére”: to sit).
In contrast, the “cede” in verbs such as “concede” comes from the Latin “cédere”: to go or yield.
For fun, I searched Google for each of the following words and got about the indicated numbers of matches:
This tells me that Web authors have written the word correctly vs. incorrectly by a ratio of 3.32:1, which is pitiful.
I recall a software manufacturer once naming its product “Supercede” and wondering whether the maker intentionally misspelled “supersede” in order to create a unique name or unintentionally misspelled the verb out of ignorance.
In any case, I found it disheartening that the maker would use a common misspelling as its product’s brand name.
Solution:
“Supersede”