その困難を克服しなければならない。

that (something or someone distant from the speaker, close to the listener; actions of the listener, or ideas expressed or understood by the listener); the; um...; er...; uh...

difficulty; distress

indicates direct object of action; indicates subject of causative expression; indicates an area traversed; indicates time (period) over which action takes place; indicates point of departure or separation of action; indicates object of desire, like, hate, etc.

conquest (problem, disease, handicap, etc. e.g. poverty, illness); overcoming; bringing under control; subjugation; victory over