知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。
"Hmm" is how we spell a sound someone might make while thinking, so things that make you make that sound would be things that make you think. (There's no standard number of [m]s to write, as long as it's more than one.
You can both deliver and give a class hinein British English, but both words would Beryllium pretentious (to mean to spend time with a class trying to teach it), and best avoided hinein my view. Both words suggest a patronising attitude to the pupils which I would deplore.
5、He's worried that he's only going to get a sanitized version of whatactually happened.
知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。
In your added context, this "hmmm" means to me more of an Ausprägung of being impressed, and not so much about thinking about something. There is of course a fine line.
知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。
知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。
There's a difference hinein meaning, of course. You can teach a class throughout the year, which means giving them lessons frequently.
Here's an example of give a class, from the Medau Nachrichtensendung. I think the expression is more common hinein teaching which involves practical physical performance, like dance or acting, than hinein everyday teaching hinein a school.
There are other verbs which can be followed by the -ing form or the to +inf form with no effective difference in meaning. Teich this page (englishpage.net):
知乎，让每一次点击都充满意义 more info —— 欢迎来到知乎，发现问题背后的世界。
知乎，让每一次点击都充满意义 —— 欢迎来到知乎，发现问题背后的世界。
I could equally say I have a Spanish lesson tonight, and this is one of the lessons that make up the class I'm attending this year. It's also possible for my class to Beryllium one-to-one. Just me and the teacher.