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The words
Plant biologists have [thought / thinking] of a clever new way to increase the size of crops by as [many / much] as 20 per cent. They have genetically modified part of the mechanism [on / in] plants that is responsible [for / from] photosynthesis. Of course, photosynthesis is the most important chemical reaction in the world. It is the process where plants use [sunlight / sunny] to change carbon dioxide [into / onto] oxygen. This means we can all [breath / breathe] . The scientists have found a way for plants to use [the / an] energy they get from sunlight better, so they [grow / grew] bigger and produce more food. Lead researcher Professor Stephen Long said his team is genetically modifying staple crops [such / much] as rice, wheat, maize and soybean – the world's biggest crops.

The scientists targeted the [mechanism / mechanic] that plants use to protect themselves from damage when the Sun's rays are too [strength / strong] . To prevent damage, plants turning their energy into [hot / heat] , which disappears into the air. However, this heat-loss process [continues / continue] even when [cloudy / clouds] block the Sun. The scientists put extra copies of the heat-loss genes into modified plants. These [addition / additional] copies speed up the heat-loss process [so / such] the plants can more quickly return to using energy to [growth / grow] . Professor Long believes this could help the world's food [needing / needs] . He said if he could get 20 per cent more food from crops, "that would greatly reduce what we see as the future pressure [on / in] food supply".

Back to the photosynthesis lesson.

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