Instructions: Point and click on the main verb in each sentence. The feedback is shown at the bottom.

  1. Graphene consists of a single layer of carbon atoms arranged in a hexagonal lattice.
  2. Ultra-high-performance concrete is a steel fibre-reinforced cement composite material with compressive strengths that exceed 150 megapascals.
  3. The first electric vehicles were developed in the mid-19th century, when electricity was among the preferred methods for motor vehicle propulsion.
  4. Cumulative global sales of highway-capable light-duty pure electric vehicles passed a global total of one million units in September 2016.
  5. Due to the associated effect of ocean acidification, deep ocean carbon storage is not currently considered a feasible method for removing carbon dioxide from the atmosphere.
  6. Using a similar technique to a refrigerator or air conditioner, ground-source heat pumps force the transfer of heat from the ground to the building.

This text is adapted from Wikipedia articles Wikipedia. This text is licensed under the Creative Commons Attribution-Share-Alike License 3.0.

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