Fill in the given words

• endangered
• project
• monitor
• challenging
• observation

1. Pandas and loggerhead turtles are[ ]
   species.
2. Tom is working on a conservation[ ]
   in the Amazon to protect the rainforest.
3. Scientists need to[ ]animals
   in the wild to check how many there are left.
4. The trek through the rainforest was quite
   [ ] . It wasn't easy walking for miles.
5. The[ ]team came to Brazil
   to study the Pink River dolphin.