Nouns derived from verbs (deverbal nouns) look deceptively like past passive participles. For example, the noun открІтие 'discovery' differs from the plural adjective открІтые 'opened' by only one letter. Similarly, the Genitive plural of the noun предложљний 'proposals' differs from the adjective предлћженный 'proposed' by only two letters. This close similarity often causes difficulty in reading. There are several ways to tell the difference:
1. The endings are different: noun vs. adjective endings. The nouns are all neuter.
  предложљни-ями (Instrumental Plural noun: 'proposals')
  предлћженн-ыми (Instrumental Plural past passive participle: 'proposed')
2. Nouns have -и- after the -т- or -н-; past passive participles do not. In other words, the noun stem ends in a vowel (и), while the adjective stems ends in a consonant (т/н).
  предложљни-е, открІти-е (nouns)
  предлћженн-ый, открІт-ый (past passive participles)
3. The noun suffix has a single -н-, but the long participial suffix has double -нн-.