The sentence is constructed by logically arranging parts P, Q, R, and S. Let's analyze each part:
- S: "metal" - This should be the subject of the sentence.
- R: "like most other materials" - This part describes a characteristic of the subject.
- Q: "expands" - This is the action that the subject undergoes.
- P: "when heated" - This part provides the condition under which the action occurs.
Now, combining these parts to form a coherent sentence, we follow the logical sequence:
- S: Start with the subject: "Metal".
- R: Add the descriptive part: "like most other materials".
- Q: Follow with the action: "expands".
- P: Conclude with the condition: "when heated".
The correctly formed sentence is: "Metal, like most other materials, expands when heated."
Thus, the correct arrangement of the sentence parts is S-R-Q-P.