a. not formal
s. not officially recognized or controlled
a. used of spoken and written language
a. 非正式的, 不拘礼的, 通俗的
[经] 非正式的, 日常使用的
1. I prefer informal meetings where everyone can share their ideas freely.
我更喜欢非正式的会议，在那里每个人都可以自由分享他们的想法。
2. She wore an informal dress to the picnic.
她穿了一件休闲的裙子去野餐。
3. The teacher encouraged informal discussions among the students.
老师鼓励学生们进行非正式的讨论。