English grammar error-spotting (article with idiom ‘‘in a … mood’’): Read the split sentence (A–D) and identify the erroneous part; choose ‘‘No error’’ only if the sentence is fully correct: ‘‘My papa is / in bad mood / today / No error.’’

Given data

• A: ‘‘My papa is’’
• B: ‘‘in bad mood’’
• C: ‘‘today’’
• D: ‘‘No error.’’

Concept / Approach
The set phrase in English is ‘‘in a bad mood’’; an article is required before a singular countable noun used in a descriptive prepositional phrase.

Step-by-Step evaluation
Part B lacks the article ‘‘a’’ → grammatical error.

Correction
‘‘My papa is in a bad mood today.’’

Common pitfalls

• Omitting articles in fixed idioms (in a hurry, in a mood, in a fix).

Final Answer
in bad mood