die Grundregel
basic rule
A fundamental, essential rule on which a system, behavior, or activity is based.
Eine Grundregel beim Autofahren ist, immer auf den Verkehr zu achten.
A basic rule when driving is to always pay attention to traffic.

basic rule
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basic rule
A fundamental, essential rule on which a system, behavior, or activity is based.
Eine Grundregel beim Autofahren ist, immer auf den Verkehr zu achten.
A basic rule when driving is to always pay attention to traffic.

'Grundregel' (basic rule) is made up of 'Grund' (here: basis, foundation) and 'Regel' (rule). It is therefore a rule that forms the foundation for everything else.
Eine Grundregel der Kommunikation ist, dem anderen zuzuhören.
A basic rule of communication is to listen to the other person.
Basic rules can be 'beachten' (observed), 'befolgen' (followed), or 'einhalten' (complied with). If you do not follow them, you 'verstößt gegen' (violate) them.
Wer gegen diese Grundregel verstößt, muss mit Konsequenzen rechnen.
Anyone who violates this basic rule must expect consequences.
The content of a basic rule is often explained with a subordinate clause beginning with 'dass' (that), or with an infinitive construction using 'zu' (to).
Es ist eine Grundregel, dass man sich vor dem Betreten die Hände wäscht.
It is a basic rule that you wash your hands before entering.
rule / period
'Regel' and 'Grundregel' both refer to something you are supposed to follow or something a field is based on. 'Regel' is more general and can be a single regulation, an instruction, or a technical principle. A 'Grundregel' is especially important: it is a basic rule that you should know first. You can confuse the words because every 'Grundregel' is also a 'Regel'. But not every 'Regel' is a 'Grundregel'. If you want to emphasize that something is very fundamental, 'Grundregel' fits better.

Eine Grundregel beim Reisen ist, wichtige Dokumente sicher aufzubewahren.
A basic rule when traveling is to keep important documents safe.
Bei der Arbeit haben wir eine neue Regel für die Pausen bekommen.
At work, we got a new rule for breaks.