I don't know what to do vs I have no idea

Quand utiliser chacun en anglais, avec le sens, le registre et des exemples.

I don't know what to do

Top 2000 (courant)

I have no idea

FamilierTop 2000 (courant)
Le plus formel: I don't know what to do
 I don't know what to doI have no idea
Prononciation🇬🇧 //aɪ dəʊnt nəʊ wɒt tə duː//🇺🇸 //aɪ doʊnt noʊ wɑːt tə du//🇬🇧 //aɪ hæv nəʊ ɪˈdɪə//🇺🇸 //aɪ hæv noʊ ɪˈdiə//
SensI am unsure about what actions to take.I don't know anything about it.
ExempleAfter hearing the news, I just said, 'I don't know what to do.'Where's the nearest coffee shop? I have no idea.
RegistreNeutreFamilier
FréquenceTop 2000 (courant)Top 2000 (courant)
Collocationsask for help, feel lost, make a decision, find a solution, seek advicehave no idea about, have no idea where, have no idea how
Antonymes-I know exactly, I am sure, I have a clear understanding
Erreurs fréquentesOmitting 'what' and saying 'I don't know to do.', Mixing up with 'I don't know how to do.', Using 'what to do' in statements instead of questions.Saying it too formally in a business meeting., Using it when a little knowledge is required., Translating it directly into another language without context.
Notes d'usageUse this phrase when expressing uncertainty or lack of direction. Appropriate in both casual and formal settings.Use this phrase in casual conversations to express lack of knowledge. Avoid in formal situations.

Vois-le dans de vrais extraits

I don't know what to do
I have no idea

Questions fréquentes : I don't know what to do vs I have no idea

Quelle est la différence entre I don't know what to do et I have no idea ?

I don't know what to do: I am unsure about what actions to take. I have no idea: I don't know anything about it.

Lequel est le plus formel : I don't know what to do et I have no idea ?

I don't know what to do est le plus formel de tous.

Peux-tu montrer un exemple de chacun ?

I don't know what to do: After hearing the news, I just said, 'I don't know what to do.' I have no idea: Where's the nearest coffee shop? I have no idea.

Puis-je utiliser I don't know what to do et I have no idea de façon interchangeable ?

Pas toujours. I don't know what to do et I have no idea sont proches et se recoupent parfois, mais elles diffèrent par le registre, la fréquence et l'usage, donc remplacer l'une par l'autre peut changer le sens ou le ton. Regarde les différences ci-dessus avant de substituer.