Read the text and fill in the gaps with the correct forms of verbs as per subject and context. Cooperation means (a) ________ (work) together for the benefit of all. Without cooperation, modern society (b) ________ (exist). Cooperation (c) ________ (see) at its best among farmers in the dry regions of some parts of Australia and America. The fields (d) ________ (irrigate) in these regions, Crops (e) ________(not grow) without water. Water (f) ________ (bring) to the fields without streams being trapped higher up. For this purpose, canals and dams (g)________ (build). The canals (h) ________ (cut) through the fields of more than one farmer. Those who (i) ________ (live) higher up the valley than the others (j) ________ (allow) to build canals through their lands in order to carry water to the fields of farmers lower down. In times of drought, all (k) ________ (be) able to share the water. Instead of (l) ________ (take) all water for themselves, the farmer on the higher land leave enough for the neighbours down the valley. Farming in dry areas (m) ________ (make) possible by such cooperation. By cooperation, farmers have learned to make even the desert ( n ) ________ (produce) crops.