21世纪.人们缺少的，也正是人们需要的（外语翻译）

In the 21st century, what people is lack of is what they really need.

In the 21st century:
21世纪，
what people is lack of:
人们所缺少的，
is
正是
what they really need:
他们所需要的（这里用they代替people的重复使用）

What human lacks, are the exact things that human requires in the twenty-first century.

in the 21th century,what is dadly off,is also what is quite needed...

What we are short of is what we need in the 21st century.

What we lace is what we need in the 21st century.

PS: 21st的st应该上标

In the twenty-first century, people are in need of what they are lacking (in).

这句话中文有毛病，所以一个个翻出来的也有毛病。