✅ Permanent means lasting or intended to last indefinitely without change (She got a permanent position at the company). 

✅ Indelible refers to something that cannot be removed, forgotten, or changed, often used metaphorically (The experience left an indelible mark on him). 

✅ Both words describe something that is lasting or unchangeable. 

✅ Permanent is used in a variety of contexts, from employment to markers, while indelible often implies a profound, lasting effect or impression (The artist's work will be featured in the museum's permanent collection; The indelible memory of their trip stayed with her).

✅ Cost refers to the amount of money required to purchase something or the effort required to achieve something (The cost of the repairs was higher than expected). 

✅ Expenditure describes the act of spending money or resources, often in a business or government context (The government's expenditure on healthcare has increased). 

✅ Both terms relate to spending money or resources. 

✅ Cost is often used in everyday contexts to discuss prices, while expenditure is more formal, typically used in financial or official contexts (The cost of groceries has risen in the last few years; The annual expenditure was carefully audited).

✅ Awful means extremely bad or unpleasant (The food at the restaurant was awful). 

✅ Abominable describes something detestable or worthy of disgust (His behavior at the party was abominable). 

✅ Both words express a strong negative reaction to something. 

✅ Awful is a more general term and can be used in various contexts, while abominable suggests a more intense or morally objectionable level of badness (The weather was awful this weekend; The abominable cruelty of the act shocked everyone).