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: Japan 's cadre of highly skilled carrier aircrews with which it began the war were , in effect , irreplaceable because of an institutionalised limitation in its training programs and the absence of a pool of experienced reserves or advanced training programs for new airmen .

SOLUTION: Japan 's highly skilled carrier aircrews could not be replaced because the training programs could not produce enough new aircrew .

PROBLEM: Each individual sheet of paper is folded into a module , or unit , and then modules are assembled into an integrated flat shape or three-dimensional structure by inserting flaps into pockets created by the folding process .

SOLUTION: Many sheets of paper are folded in identical shapes , and they are then put together by inserting flaps into pockets .

PROBLEM: A siddur ( Hebrew : -RSB- ; plural siddurim , -RSB- ) is a Jewish prayer book , containing a set order of daily prayers .

SOLUTION:
A siddur is a Jewish prayer book .