TASK DEFINITION: In this task, we ask you to rewrite a sentence in simple English without changing its general meaning. Essentially, you want to make the sentence easier to read by using simpler words, utilizing more straightforward sentence structures, and omitting non-essential information etc.
PROBLEM: The lanthanide elements are the group of elements with atomic number increasing from 57 ( lanthanum ) to 71 ( lutetium ) .

SOLUTION: From lanthanum ( 57 ) to lutetium ( 71 )

PROBLEM: The most important is the Constitution of the Commonwealth of Australia , which is referred to as the " Constitution " in the remainder of this article .

SOLUTION: The most important is the Constitution of the Commonwealth of Australia .

PROBLEM: Havana ( ; Spanish : " La Habana " -RSB- ) is the capital city , largest city , province , major port , and leading commercial center of Cuba .

SOLUTION:
Havana is the capital city of Cuba .