a helpful or good effect, or something intended to help

• benefit
• landmark
• invention
• innovation
• housing

something difficult to accomplish

• challenge
• benefit
• landmark
• invention
• innovation

an agreement in an argument in which the people involved reduce their demands or change their opinion in order to agree

• compromise
• challenge
• benefit
• steel
• staircase

problem

• difficulty
• compromise
• challenge
• benefit
• steel

a choice between two unpleasant or difficult options

• dilemma
• difficulty
• compromise
• challenge
• benefit

a person or animal that lives in a certain place

• inhabitant
• dilemma
• difficulty
• compromise
• challenge

the basic systems and services, such as transport and power supplies, that a country or organization uses in order to work effectively

• infrastructure
• inhabitant
• dilemma
• difficulty
• compromise

separation from others; aloneness

• isolation
• infrastructure
• inhabitant
• dilemma
• difficulty

a subject or problem that people are thinking and talking about

• issue
• isolation
• infrastructure
• inhabitant
• dilemma

a great city that is made up of several large and small cities

• megacity
• issue
• isolation
• infrastructure
• inhabitant