noun - a greedy desire for wealth, power, possessions

adjective - someone/something that is essential, other people can hardly manage without them

adjective - extremely difficult to solve

adjective - feeling embarrassed and ashamed

adjective - tests, rules or processes that are strict

adjective - done very carefully and with great attention to detail

noun - a sudden and unaccountable change in attitude or behaviour

noun - something that is helpful or beneficial

adjective - very strict or severe (laws, rules..)

adjective - covered with many sharp, pointed parts (animals, plants.. )

verb - to make something weaker and less effective

adjective - full of tiny holes, easily penetrated

verb - to make something such as an action or a task slow or difficult

noun - a place where large amounts of waste are buried under the earth

noun - the process of taking part in something