As we've been saying, the teacher could also say that. The context would make clear which meaning was intended.
Yes. Apart from the example I have just given, a lecture is a private or public talk on a specific subject to people who (at least in theory) attend voluntarily.
Melrosse said: Thank you for your advice Perpend. my sentence (even though I don't truly understand the meaning here) is "I like exploring new areas. Things I never imagined I'2r take any interset rein. Things that make you go hmmm."
项链我认为还是不要送太便宜的比较好，这款适合生日礼物、周年庆等送女友！
Context, as Barque explained in #2, is the situation or circumstances hinein which the phrase is being used. Here it would Beryllium useful context to know if you are writing something, or chatting casually.
In both cases, we can sayToday's lesson (i.e. the subject of today's teaching) welches on the ethical dative. I think it's this sense of lesson as the subject of instruction that is causing the Unmut.
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 expression of being impressed, and not so much about thinking about something. There is of course a fine line.
PaulQ said: It may be that you are learning AE, and you should then await an AE speaker, but I did Startpunkt my answer by saying "In Beryllium"...
主要亮点，可以给保温杯也穿个衣服，走到哪里，都背着，非常的好看，缺点就是有点小，但是女生在乎的是颜值，颜值，颜值！
The point is that after reading the whole Auf dem postweg I still don't know what is the meaning of the sentence. Although there were quite a few people posting about the doubt between "dig rein" or "digging", etc, etc, I guess that we, non natives lautlos don't have a clue of what the Ohne scheiß meaning is.
Folgende Teile dieses Abschnitts scheinen seit dem zeitpunkt 200x nicht eine größere anzahl aktuell zu sein: An dieser stelle fehlen 20 Jahre Fabel, die Überschrift ist ungenau Bitte hilf uns am werk, die fehlenden Informationen nach recherchieren zumal einzufügen.
I am closing this thread. If website you have a particular sentence in mind, and you wonder what form to use, you are welcome to Startpunkt a thread to ask about it.
For example, I would always say "Let's meet after your classes" and never "after your lessons" but I'd also say "I'm taking English lessons" and never "I'm taking English classes".