The use of the negative "il faut" version, i.e., "il ne faut pas qu'il", is a real head-banger. I struggled with this myself and have learned that it actually is to be understood as "he must not", rather than the straight-on "it is not necessary that he...." The latter is not only awkward English, it is actually wrong.
I just had that problem. The first time it said in English "It is necessary that he not enter. . ." so I put "il faut qu'il n'entre pas" and I got it wrong because it said it wanted "il ne faut pas". Then this time, in french, I got "Il ne faut pas. . ." so I put "it is not necessary that he enter my room" and it counted it wrong saying it wanted "It is necessary that he not enter my room". Both are grammatically correct, but they have the translations switched.
How do you say "it is not necessary" then? This just totally confused me. I thought you use the Don't + Enter instead of Don't + necessary?? Pease help.
In spanish this translate to that it is not necessary for him to enter. Like saying, dont bother him rather than 》it is important for him not to enter the room because the person saying it wants privacy.
Could someone please clarify the comments regarding the correct meaning here. As gdlh said a year ago - ' "It is not necessary that he enters my room! It is necessary that he does not enter my room!" These two solutions have different meanings; which one is it really?' And how do you express the other?
Let me stress once more: Neither French nor English are logically coherent here. Quoting from https://www.englishclub.com (which is British): "Must not expresses prohibition - something that is not permitted, not allowed. The prohibition can be subjective (the speaker's opinion) or objective (a real law or rule). Look at these examples:
I mustn't eat so much sugar. (subjective) You mustn't watch so much television. (subjective) Students must not leave bicycles here. (objective) Policemen must not drink on duty. (objective)".
Just to compare: In my native language, Danish, we use "må ikke" (may not) for "you are not allowed to".
Although it seems logical that if "Il faut" means "it is necessary", then "il ne faut pas" should mean "it is not necessary", but I must inform you that this is simply not the case.
"Il ne faut pas" categorically means, "it is necessary that (x) NOT occur", "it is forbidden", "he must not", or whatever absolute negation you care to use.