高级词汇invisibly，副词词性，意思是无形地，例如：

1、Paid no attention， allowed emotion to leave unscrupulously and invisibly how much recollection.不经意间，任情感恣意，无形中留下了多少回忆。

3、He looked at me and nodded， almost invisibly.他看着我点了点头，几乎让人看不出来。

4、Space travel can be so delightful but at the same time invisibly dangerous.太空旅行可以非常令人愉快，但同时又存在无形的危险。