Complete the text with suitable prepositions.

Email has brought (a) _____ a revolution (b) _____ modern communication. Messages can be transmitted (c) _____ one country to another (d) _____ seconds. It is far cheaper than telephone calls. Trade and commerce has become greatly dependent (e) _____ this speedy mode (f) _____ communication. It has, however, not reached everyone, especially (g) _____ developing countries (h) _____ ours, as most people cannot afford (i) _____ have a personal computer. But even here, people have started using commercially operated email facilities (j) _____ important purposes.