(used after an adverb such as 不, 大, 稍 etc, and before a disyllabic verb, to indicate that the action of the verb is applied to sth or sb previously mentioned)
to apply (restrictions etc) to (sb)
to give (support, consideration etc) to (sth)
to increase
to augment
to append
Learn Stroke Order
See how to write "加" with stroke-by-stroke animation