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