As 'gold' is an uncountable noun, the adjective it takes will be 'less' rather than 'fewer'. As 10,000 is a countable number, its adjective will be 'fewer'. Choices (b), (d) and (e) are, therefore, eliminated. George has not written anything for some time; 'some' here is adjective for the noun 'time' and hence a separate word. The fourth blank takes the word which answers 'when'. Therefore 'sometime' which represents an unspecified time is apt. The fifth blank takes, an adverb, which means occasionally i.e. 'sometimes'.