Both present participles (ing) and past participles (ed) can be used as adjectives. But be careful not to confuse them. Present participle adjectives, tiring, boring, interesting, are active and mean ‘having this effect’. Past participle adjectives, tired, bored, interested, are passive and mean ‘affected in this way’. In other words, someone is -ed if something (or someone) is -ing. Or, if something is -ing, it makes you -ed.
Jane is bored because her job is boring. Jane’s job is boring so Jane is bored.