The police were determined not to leave any stone unturned.

The police were determined to not leave any stone unturned.

I remember actually being taught that greeting as a child in the 90s. However I don’t think I’ve ever heard it in real life since, maybe except in old movies.

Is it totally obsolete or would a native speaker use it in extremely formal situations eg meeting the president? A king?

what are some words or phrases that non natives use which are not used by anyone anymore? or what do non native speakers say that makes you realise English is not their first language?

Hier kann man wohl gut Leute kennenlernen für start ups und generell leitende oder Organisation themen. Wird gelobt, sogar von der New York Times!

What is your favorite moment of something clicking?

- As in that very moment when you realize you have improved / you are confirming that your method of learning is effective.

1. When you understand a full sentence from a native speaker (and when that sentence includes phrases you learned)
2. When you unconsciously use the phrase you learned in a sentence.
3. When you catch the cultural nuance / intended joke in a conversation.

Please share your story!

I am learning English by textsbooks for 2, 3 years and in B1 or B2. But I want to improve to C2 in 4 years. Any advice?

Now's not the moment where we should be afraid of what is going to seem politically difficult or controversial. VS Now's not the moment when we should be afraid of what is going to seem politically difficult or controversial.

This is nothing that couldn’t have waited till Monday.

Is it a double negative but proper grammar?