Question

Iron is ......useful thing.(a/an)
which is correct ​

Answer 1

Answer:

Iron is a useful thing.

reason =Definite article includes the and indefinite includes a and an. The word "a" is used before the consonants and "an" with vowels.

Answer 2

Answer:

Iron is an useful thing

Explanation:

Here,

we will use "an" because in word useful u" is a vowel and "an" is used with vowels

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