On the bottom rung are an estimated 300, 000 grass-roots organizations that are unregistered or set up as commercial enterprises.

最底层的是大约30万个草根组织，它们并没有注册或者是作为商业性的企业建立起来的。

youdao

The bottom of his trousers swayed heavily with his strides as they collected the dew from the dense grass and brush.

他的裤脚随着他的步幅沉重地摇摆，因为它们从茂密的草丛和灌木上沾到露水。

youdao

They looked and saw a little hollow in the grass, with a grassy bottom, warm and dry.

他们看见草中有个小坑，坑底长满温暖而干燥的草。

youdao

A piece of sod has grass on the top and soil on the bottom.

VOA: special.2009.07.07

Real school choice, with real grass-roots, bottom-up reform means that a community of people who care about their public goods deeply want to work to make those goods better.

FORBES: School Choice and the Value of Public Goods

The bottom is mainly brilliant white sand or greenish grass, but we were searching for the vaguely brown and yellow hues that indicate the rocks and coral where Caribbean spiny lobster (commonly referred to as "bugs" for their insect-like appearance) live.

BBC: Lobster diving in the Abacos