Error Spotting – Choose the part (A–D) that contains a grammatical error, or choose No error if the sentence is fully correct. Sentence (parts correspond to options below): A) Day in and day out B) he keep telling C) his friends that D) he wants to go abroad.

Introduction / Context:
This item checks present simple agreement with a third-person singular subject. In the simple present, the base verb generally takes -s or -es with he, she, or it.

Given Data / Assumptions:

• Subject: he
• Verb phrase provided: keep telling
• Temporal adverbial: Day in and day out, indicating habitual action

Concept / Approach:
For habitual actions with third-person singular subjects, the main verb in the simple present must be inflected with -s: keeps. The progressive telling remains unchanged as a present participle following keeps.

Step-by-Step Solution:

Verification / Alternative check:
Replace the subject with plural: They keep telling is correct. With he, the correct form is he keeps telling, which confirms the error in the original fragment.

Why Other Options Are Wrong:

• A) Idiomatic adverbial phrase indicating frequency.
• C) Object and complement clause introducer are correct.
• D) Verb in the subordinate clause agrees with he and is correctly inflected.

Common Pitfalls:
Omitting -s with third-person singular in habitual statements is a frequent error, especially when an adverbial opening distracts from the agreement rule.

Final Answer:
Option B contains the error. Use keeps instead of keep.