Now the Earth needs our help more than ever before. Despite the constant development of technology and medicine, we may face problems that have arisen for a long time. Now we have a lot of global problems that can eventually lead to our death. Many species of animals and fish are on the verge of extinction, the water in the ocean and seas is polluted, and small lakes and rivers dry up, forests are destroyed. Problem solving maybe our strength can't be underestimated, we have to think and start doing something. As humans, we have a great opportunity to help our planet and ourselves.
The - определенный
А - неопределенный