Fill in the blank with the correct phrasal verb particle: Rita promised to come but she never turned ________.

Introduction / Context:
This question focuses on phrasal verbs, which are combinations of a verb with a particle (like up, down, in, out) that create a specific idiomatic meaning. Here the verb turn is followed by a blank that must be filled with the correct particle to complete a very common expression about someone failing to arrive.

Given Data / Assumptions:
- Sentence: Rita promised to come but she never turned ________. - Options: in, out, down, up. - Context: Rita promised to come, but in fact she did not appear.

Concept / Approach:
The phrasal verb turn up means to arrive or appear, especially at a meeting, event, or place where one is expected. The negative form never turned up means did not come or did not appear. Other combinations with turn, such as turn in, turn out, and turn down, carry different meanings that do not fit this context, so they cannot complete the sentence correctly.

Step-by-Step Solution:
Step 1: Interpret the situation: Rita promised to come but did not arrive. Step 2: Recall the phrasal verb turn up, which is used when someone appears at a place. Step 3: Insert up: Rita promised to come but she never turned up. Step 4: Check alternative meanings: - Turn in can mean submit or go to bed. - Turn out can mean result or be present in numbers. - Turn down means refuse or reduce volume. Step 5: None of these match the intended sense of failing to arrive.

Verification / Alternative check:
Consider similar sentences: Many guests turned up late for the party, or She did not turn up for the interview. In each case turn up clearly describes arrival. If we say She never turned up, it naturally means she did not appear. This confirms that up is the only correct particle for the given sentence.

Why Other Options Are Wrong:
In in option A, turned in would change the meaning to submitted something or went to sleep, which is unrelated to coming to a place. Out in option B would produce turned out, a different phrasal verb often used to talk about results or attendance, but the structure here does not support that meaning. Down in option C gives turned down, which is used for refusal or lowering something, not for arriving.

Common Pitfalls:
A common problem with phrasal verbs is relying on literal meanings of particles. For example, learners may think out suits leaving or not being there, but phrasal verbs are idiomatic and must be learned as fixed combinations. Memorising common expressions like turn up, show up, and come over will make these questions much easier.

Final Answer:
The correct phrasal verb is turned up, so the answer is up.