1. Present simple tense: Used throughout to express general opinions and facts, e.g., "I don’t think smiling always means someone is genuinely friendly."
2. Complex sentences: Use of subordinate clauses, e.g., "even if they don’t smile much," and "while a smile can be a good sign," to show contrast and add depth.
3. Modal verbs: "can" is used to express possibility, e.g., "a person can show friendliness through actions."
4. Passive voice: "smile out of politeness or habit" (implied passive meaning, though not strictly passive structure).
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