Instructions: The sentences below contain additional information, such as examples, that should be separated with commas from the main sentence. The text may also include introductory phrases before subjects that also require commas. Add commas when needed.

  1. Historically a handheld mobile radio telephone service was envisioned in the early stages of radio engineering.
  2. In 1917 Eric Tigerstedt a Finnish inventor filed a patent for a "pocket-size folding telephone with a very thin carbon microphone" which was only one of the 71 patents he was awarded in several countries between the years 1912 and 1924.
  3. The first handheld mobile phone was demonstrated by John F. Mitchell and Martin Cooper of Motorola in 1973 which they achieved using a handset weighing approximately 2 kilograms i.e. 4.4 pounds.
  4. The first mobile news service which was delivered via SMS was launched in Finland already in 2000.
  5. In many countries mobile phones are used to provide mobile banking services which may include the ability to transfer cash payments by secure a SMS text message.

This text is adapted from a Wikipedia article Mobile phone. This text is licensed under the Creative Commons Attribution-Share-Alike License 3.0.

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