Sentence:  In a mobile society , congregational health depends on a constant process of recruitment ; this recruitment , however , must follow the pattern of economic integration or it will disrupt the congregation ; therefore , the recruitment or missionary outreach of the congregation will be co-optation rather than proclamation - like <WSD>elements</WSD> will have to be assimilated . 
Meaning of the word marked with <WSD> tags:  an abstract part of something