In the following question, a sentence is given with a part in bold. The given phrase in bold may contains an error. The options following can replace the incorrect phrase. The correct phrase that is to be replaced will be the answer. If the sentence is correct, then select ‘No improvement required’ as the answer.

I and my friend have been living here for tens years.

Correct option is D

In the given sentence, the highlighted phrase is incorrect. Numerical adjectives are typically not used in the plural form. Numerical adjectives, such as "one," "two," "three," etc., are used to indicate specific quantities or numbers. They are inherently singular and do not change form based on the noun they modify.
(a) since ten years: This option uses the preposition "since" inappropriately with a duration. "Since" is used to indicate a specific point in time, not a duration. Therefore, this option is incorrect.
(b) since past ten years: This option is incorrect because it combines "since" with "past" to indicate a duration of time. However, "past" is not required in this context. Additionally, "since" should be followed by a specific point in time, not a duration.
(c) for ten years ago: This option is incorrect as it combines "for" with "ten years ago." The correct usage is either "for ten years" or "ten years ago," but not a combination of both.
(d) for ten years: This option is the correct answer. It accurately replaces the incorrect phrase with "for ten years," indicating the duration of time for which the speaker and their friend have been living there.
After replacement the sentence will be, “I and my friend have been living here for ten years.”