Final answer:
The question asks about declining future active participles, which seems to be a confusion of concepts, as English participles do not decline. The detailed answer corrects this and explains the usage of active and passive voice, as well as participial phrases, in English.
Step-by-step explanation:
The question posed appears to be mistyped, requesting information on how future active participles are declined. However, the information provided deals with the passive voice, active voice, and participial phrases.
These are separate grammatical concepts. In English, participles can be either active or passive but do not decline as they might in other languages with more inflectional morphology. Instead, participles in English are used to create various verb tenses, both in active (active voice) and passive forms (passive voice), and can function as adjectives or adverbs in participial phrases.
An example of an active participial phrase is 'Skipping along the forested path, the dwarfs whistled in a merry chorus.' In this sentence, 'Skipping' is a present participle used adjectivally to describe the dwarfs.
A passive voice construct might be 'The house was argued by Jose to be no place for a dance party,' where 'argued' is a past participle used in a passive voice structure with 'was' as the auxiliary verb showing that the subject ('the house') is acted upon rather than performing the action.