As dem. adv. with temporal function: (a) with ref. to a past event or events or a period of time: at that time, during that time, then; also, with ref. to a specific day or year in the past: on that……

Used to introduce a clause having a finite verb and expressing a comparison or contrast: (a) in constructions with a comp. adj., adj. as noun, or adv. in the comp. degree: than; (b) in constructions……

Referring to a specific member of a class and used anaphorically, pointing to a person or thing previously mentioned: the, that, this: (a) with noun; also with noun used as indirect obj. [1st quot.]……