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科学素养与生活应用·英语30篇(6)

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Why Bridges Don’t Fall Down

Why Bridges Don’t Fall Down

为什么桥梁不会倒塌

  1. Engineers plan bridges very carefully first.
  2. Strong steel and concrete hold heavy weight.
  3. Arches and triangles spread force evenly.
  4. Pillars push down into solid ground or rock.
  5. Wind and traffic cause small, safe movements.
  6. Sensors check stress and temperature daily.
  7. Workers fix tiny problems before they grow.
  8. Good design keeps people safe for many years.
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