No it is not there is only 2 prepositions that start with "C". That is the answer if you meant if it was a preposition. If you are asking if it is a prepositional phrase then the answer is also NO because a phrase has to have more than one word.
The phrase of "word of the day" means that there is a new word for each day for most people to learn. It is meant as a learning word for people to use & educate other people of its use.
The phrase "but I learn a lot" has five syllables.
Cowboys loved a colorful phrase! This meant lies and tall tales. They meant no more than the dust in the corral.
The phrase trans ocean is meant to mean across the ocean. Trans ocean is meant to be the same as transocean, which is not a word but a shorter version of transoceanic, to which it is meant to have a similar meaning.
One may learn more about Discover card service from Discover Network. They have a very good FAQ that is meant to help consumers learn all about their card services.
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The phrase a wallpaper on your desktop can mean that your desktop is covered in papers. This can be meant on your computer or your actual desk.
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This is a phrase, not a question. We can't guess what you meant to ask about it. Please try again and be more specific.
The phrase means that the question is difficult to answer. Like this one.
You smell heavenly or you smell very good :) Is this what you meant?