Question

A. Rewrite and the correct the sentences if it is wrong
i.
You can always open mail from unknown source.​

Answer 1

Answer:

it is grammatically correct..but you shouldn't do this in real

Answer 2

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• You can always open mail from unknown source.

:⟶ You can always open mail from an unknown source.

$\huge\mathrm{Explanation:}$

• Articles are used before nouns or noun equivalents and are a type of adjective. 
• They are an important part of making the sentence look more effective and catchy.
• 'An' is an indefinite article and is used before a noun that is general or when its identity is not known.

Types of articles :

1. Definite article → the
2. the indefinite article → a, an

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