The mission of the U.S. Environmental Protection Agency is to protect human health and to safeguard the natural environment air, water, and land upon which life depends.
(The mission of the U.S. Environmental Protection Agency; is; to protect human health and to safeguard the natural environment air, water, and land) (land; depends; life)
The mission of the U.S. Environmental Protection Agency land
is depends
to protect human health and to safeguard the natural environment air, water, and land
life