1. Infinitive of purpose: "to improve their living environment" uses the infinitive form to clearly express the reason or purpose for growing plants.
2. Present simple tense: The answer consistently uses the present simple tense (e.g., "Plants add beauty and life," "They also help purify the air") to state general facts and common beliefs.
3. Causative structure: "which makes the atmosphere feel fresher and healthier" uses the causative verb "make" followed by an object and a bare infinitive, showing a more advanced grammatical structure.
4. Modal verb for emphasis: "can really lift your mood" uses the modal "can" to express possibility or ability, which adds nuance to the statement.