An is the form of a you use when the word after it starts with a vowel.
a car, an apple.
An and a are used with singular countable nouns: a girl, an armadillo
We don't put an or a in front of plural or countable nouns because a/an means 'one'.
a girls, a milk
i do not know how to use embalming in a sentence. (there is the sentence)
So- you are asking when to use 'when' in a sentence. When you are asking how to use when in a question, you are already using when in a sentence, because a question actually is a sentence. I like to use when in a sentence whenever I like.
How do you use sedition in a sentence
use contingency in a sentence?
use adainty as sentence
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use ize in sentence
This is how you use mound in a sentence
enjoin use in sentence
how can we use travelogue in the sentence
Use it in a big sentence.