In the following question, one part of the sentence may contain an error. Identify which part has the error or choose "No error" if the sentence is correct: "Please put on a note (A) / declaring that (B) / Monday will be a holiday. (C) / No error (D)".

Introduction / Context:
This is an error spotting question from English grammar. You are given a sentence divided into four labelled parts and must decide which part contains a grammatical or idiomatic error. Such questions are common in competitive exams to test knowledge of standard English usage and common collocations, especially with phrasal verbs like "put up".

Given Data / Assumptions:

• Full sentence: "Please put on a note declaring that Monday will be a holiday."
• Part (A): "Please put on a note"
• Part (B): "declaring that"
• Part (C): "Monday will be a holiday."
• Part (D): "No error"
• The context is an instruction to display or post a notice.

Concept / Approach:
The key concept here is correct usage of phrasal verbs. In English, "put up a note" or "put up a notice" is the standard phrase meaning to display or post a written announcement so that others can see it. The phrase "put on a note" is not idiomatic in this context. Therefore, we must identify the incorrect phrasal verb and recognise the correct expression.

Step-by-Step Solution:
Step 1: Read the sentence for overall meaning. The speaker wants someone to display a written message announcing a holiday. Step 2: Examine part (A) "Please put on a note". In standard English, we say "put up a note" when we mean to stick or display a note on a board or wall. "Put on a note" does not convey that meaning. Step 3: Check part (B) "declaring that". This is grammatically correct and clearly links the note to the message it contains. Step 4: Check part (C) "Monday will be a holiday." This is a correct and clear independent clause. Step 5: Since only part (A) contains an error, part (D) "No error" cannot be the answer. Step 6: Conclude that the error lies in part (A). The corrected sentence should be: "Please put up a note declaring that Monday will be a holiday."

Verification / Alternative check:
Replace "put on" with "put up" and read the sentence again: "Please put up a note declaring that Monday will be a holiday." This sounds natural and matches the typical usage in notices and instructions. No other part sounds incorrect or awkward, confirming that only part (A) contains the error.

Why Other Options Are Wrong:
Part (B) is correct because "declaring that" accurately introduces the content of the note. Part (C) is correct as it expresses a clear future statement, "Monday will be a holiday." Part (D) "No error" is wrong because there is in fact an error in part (A).

Common Pitfalls:
Many learners confuse phrasal verbs that use similar prepositions, such as "put on" and "put up". "Put on" usually refers to wearing clothes or operating electrical devices ("put on a coat", "put on the light"). "Put up" is used for displaying or constructing something, such as putting up a poster or putting up a tent. Remembering these collocations helps you avoid such errors in exams and real communication.

Final Answer:
The error is in Part (A) – "Please put on a note", which should be "Please put up a note".