this
det.det. the person, thing, or idea that is very close to you or that you just mentioned. You use it to point out something specific in the present moment.
det. a demonstrative used to identify a specific person, object, or concept currently present or recently mentioned. Functions as a deictic marker to establish immediate spatial or temporal proximity.
This coffee is much better than the one I had yesterday.
I am reading this book because my professor recommended it during our last lecture.
While many scholars argue for a radical shift in policy, this particular study suggests that incremental changes are more sustainable in the long term.
From Middle English this, from Old English þis (neuter demonstrative), from North Sea Germanic base þa- "that", from Proto-Germanic þat, from Proto-Indo-European tód, extended form of demonstrative base to-; + North-West Germanic definitive suffix -s, from Proto-Indo-European *só (“this, that”). Cognate with Scots this (“this”), Saterland Frisian dusse (“this”), West Frisian dizze (“this”), German dies, dieses (“this”), Old Gutnish þissi (“this”).
Typically precedes a singular countable noun or an uncountable noun. When used without a following noun, it functions as a demonstrative pronoun.
I like these bookI like this bookThis must be used with singular nouns; use 'these' for plural nouns.