Englishfor English speakers
a
Determinative
—
A is used when the following word could be any of a certain type.
Compare "A book I saw on the shelf" and "The book I gave you yesterday".
a
Noun
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A is the first letter of the alphabet.
The letter "a" comes before "b".
—
In some schools, an A is a very high grade.
Ron got an A on his earth science test.
week
Noun
—
A week is a period of time that lasts seven days.
There are seven days in one week.
Examples a week examples
How do I use a week in a sentence?
Simple sentences
You'd be surprised what you can learn in a week.
Movie subtitles
I was a student up until last week.