(i) Consider each couple as a single unit or 'block'. There are 7 such blocks. These blocks can be arranged in a line in \(7!\) ways. Within each block, the two people can be arranged in \(2!\) ways. Therefore, the total number of arrangements is \(7! \times 2^7 = 645,120\).

(ii) Treat the 7 friends as one group and the 7 partners as another group. These two groups can be arranged in \(2!\) ways. Within each group, the individuals can be arranged in \(7!\) ways. Therefore, the total number of arrangements is \(7! \times 7! \times 2 = 50,803,200\).