Complete the text with suitable prepositions: —

The environment plays an important role (a) _____ our lifE- (b) _____ short, what we have (c) _____ us including people, houses, air, water, etc. is called environment. These are the main elements (d) _____ our environment. (e) _____ ensuring sound life the balance (f) _____ the natural elements is very significant. Sometimes (g) _____ lack of knowledge, we don't realise the importance (h) _____ it. As a result, we are polluting our environment unknowingly. Living (i) _____ a polluted environment is undoubtedly a matter (j) _____ great regret.