Fill in the gaps with the correct forms of verbs as per subject and context:

Festivals (a) ______ (be) common to all societies and cultures. With the change of social and economic structures, the nature of festivals also (b) ______ (change). But some festivals (c) ______ (be) so deeply (d) ____ (root) in the social organism that they (e) _______ (continue) to entertain from generation to generation. Some of the festivals (f) (bear) the mark of the community and nationality, some (g) _____ (have) the stamp of religion and again some (h) _______ (bear) the impression of politics. The festivals, which (i) _____ (get started) in the primitive society centering on the prayer for food (j) _____ (have) now been (k) ______ (fill) with various colours and varieties. The main foundation of festivals (l) _____ (be) ritual and most of the ancient rituals (m) _______ (be) collective activities. Many of the rituals were (n) ______ (relate) to agriculture and were determined by lunar months.