In the following questions, a sentence has been divided into four parts and marked a, b, c and d. One of these parts contains a mistake in grammar Idiom or syntax. Identify that part and mark it as the answer.
The train is unusually late today
for it has been announced just now
that it will arrive in a hour
on platform number three
Correct Answer :
C. that it will arrive in a hour
an hour. An is used before a word beginning with a vowel sound.