一,not only...but also...連接兩個并列分句時,前一個要倒裝,后一個不倒裝.但連接并列主語或并列謂語時則不用倒裝.例如：
Not only is the son fond of watching cartoons,but the parents take great interest in them.
Not only she but also her husband does housework on weekends.
Eric not only speaks but also writes well in English~
此句Not only I wish short leave中的I wish short leave可以看做是一個主語,所以這里就不用倒裝!
二,short leave可以譯為“短暫的離開”這里可以翻譯的靈活點通俗點“離開一小會”
所以原句的翻譯是：
不僅是我希望離開一會~