In the sentence, identify the segment which contains the grammatical error.   Unfortunately, I lost interested halfway through the film.

The grammatical error of the sentence is in option A. ‘Interested’ is an adjective which means ‘having or showing interest; especially curiosity or fascination or concern’. Here, we don’t need an adjective as it is not being modified by a noun in the given sentence. And, a noun is needed after the verb “lost” to show what had been lost i.e. interest. Interest is a noun that means the feeling of wanting to give your attention to something or of wanting to be involved with and to discover more about something. For example, I’ve always had an interest in astronomy. She never seems to show any interest in dancing. In order to make the sentence correct, replace “interested” with “interest”. Correct sentence: ‘Unfortunately, I lost interest halfway through the film.’