| after | después de que |
| animal | el animal |
| as soon as | en cuanto/tan pronto como |
| before | antes de que |
| bird | el ave/el pájaro |
| cat | el gato |
| climate change | el cambio climático |
| cloud | la nube |
| conservation | la conservación |
| container | el envase |
| cow | la vaca |
| crater | el cráter |
| danger | el peligro |
| deforestation | la deforestación |
| desert | el desierto |
| ecological | ecológica/ecológico |
| ecologist | el ecologista/la ecologista |
| ecology | la ecología |
| ecotourism | el ecoturismo |
| environment | el medio ambiente |
| extinction | la extinción |
| factory | la fábrica |
| fish | el pez/los peces |
| flower | la flor |
| global warming | el calentamiento global |
| government | el gobierno |
| grass | la hierba |
| i hope that | ojalá |
| in case | en caso de que |
| it is a shame | es una lástima |
| it is impossible | es imposible |
| it is improbable | es improbable |
| it is not certain | no es cierto/no es seguro |
| it is not possible | no es posible |
| it is not probable | no es probable |
| it is not true | no es verdad |
| it is obvious | es obvio |
| it is ridiculous | es ridículo |
| it is sad | es triste |
| it is strange | es extraño |
| it is terrible | es terrible |
| jungle | la selva |
| lake | el lago |
| land/soil | la tierra |
| law | la ley |
| made of aluminum | de aluminio |
| made of glass | de vidrio |
| made of plastic | de plástico |
| monkey | el mono |
| natural resource | el recurso natural |
| nature | la naturaleza |
| not to believe | no creer |
| not to deny | no negar |
| not to doubt | no dudar |
| nuclear/solar energy | la energía nuclear/la energía solar |
| overpopulation | la sobrepoblación |
| plant | la planta |
| pollution | la contaminación |
| provided that | con tal de que |
| pure | pura/puro |
| rain forest | el bosque tropical |
| recycling | el reciclaje |
| renewable | renovable |
| river | el río |
| sea | el mar |
| sky | el cielo |
| so that | para que |
| solution | la solución |
| star | la estrella |
| stone | la piedra |
| sun | el sol |
| there is no doubt | no cabe duda/no hay duda de |
| to avoid | evitar |
| to be affected | estar afectada/estar afectado |
| to be afraid | temer |
| to be happy | alegrarse |
| to be polluted | estar contaminada/estar contaminado |
| to be sorry | sentir |
| to breathe | respirar |
| to conserve | conservar |
| to control | controlar |
| to destroy | destruir |
| to develop | desarrollar |
| to discover | descubrir |
| to hope | esperar |
| to hunt | cazar |
| to improve | mejorar |
| to pick up | recoger |
| to pollute | contaminar |
| to protect | proteger |
| to recycle | reciclar |
| to reduce | reducir |
| to regret | arrepentirse |
| to solve | resolver |
| to stop doing | dejar de |
| to take care of | cuidar |
| trail | el sendero |
| tree | el árbol |
| turtle | la tortuga |
| unless | a menos que |
| until | hasta que |
| valley | el valle |
| volcano | el volcán |
| whale | la ballena |
| when | cuando |
| without | sin que |