1. Ships spill oil in oceans and rivers. Many aquatic animals and plants die (lead to) 2. We are unable to see the stars in the sky. Light pollution occurs. (makes)

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1. Ships spill oil in oceans and rivers. This leads to the death of many aquatic animals and plants.

Hoặc : Ships spill oil in oceans and rivers, which leads to the death of many aquatic animals and plants.

2. Light pollution makes us unable to see the stars in the sky.