Original: In 1972, the Hong Kong government authorised construction of the Initial System, a 20-kilometre system that roughly translates to the Kwun Tong Line of today.
Simplified: In 1972, the Hong Kong government authorised construction of the Initial System, a 20-km system that roughly translates to the Kwun Tong Line today (except the line now extends to Tiu Keng Leng).