Complete the sentences with proper words.
1. Once a man called John f________ lots of gold in a cave, but he only picked some pieces and went home.
2. Some i________ build their homes under the ground.
3. Sometimes goldfish may eat bread but it is not g_________ for them.
4. P________ are very important living things.
5. We can plant more trees, farm less, make the soil(土壤) stronger to s______ the Sahara Desert(撒哈拉沙漠) growing.