✅ Notice means to become aware of something or someone through observation (She didn't notice the typo in her report). 

✅ Perceive refers to becoming aware of or interpreting something through the senses or the mind (He could perceive the tension in the room).

✅ Both words involve awareness of something through observation or experience. 

✅ Notice is often used for physical or immediate observation, while perceive can include deeper understanding or intuition (He didn't notice the changes in her mood; She could perceive the hidden meaning behind his words).

✅ Steady describes something that is firmly fixed, constant, or reliable (She maintained a steady pace during the race). 

✅ Unwavering means not changing or becoming weaker, especially in support or belief (His unwavering dedication to his family was admirable). 

✅ Both words imply consistency and reliability. 

✅ Steady can describe both physical actions and metaphorical traits, whereas unwavering typically refers to mental or emotional steadfastness (He kept a steady hand while painting; Her unwavering faith inspired others).

✅ To begin means to start or initiate something (They will begin the project tomorrow).

✅ To undertake refers to committing oneself to and beginning a task or responsibility that may take a long time (She decided to undertake the restoration of the old mansion).

✅ Both terms describe the start of an action or task.

✅ Begin is a more general term used in many contexts, while undertake implies a formal or serious commitment to a task or project (She will begin her painting class this week; They will undertake the construction of the new bridge).