I believe that Maya is right.
The that-clause is the object of believe.
Satzbausteine
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
Use that, wh-, and if/whether clauses as subjects, objects, complements, and reported content.
A noun clause = one whole idea used as a noun
Main sentence needs an idea
│
▼
┌───────────────┐
│ IDEA CLAUSE │
└───────────────┘
▲
pick the opener by meaning:
that = a stated idea / fact
I believe that Maya is right.
wh- = missing information
We don't know where the file is.
if/whether = yes/no uncertainty
I'm not sure if the door is locked.
Inside the idea clause:
normal statement order, not question order.
Choose the opener by the kind of idea, then keep normal statement order inside the noun clause.
I believe that Maya is right.
The that-clause is the object of believe.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
We don't know where the file is.
The wh-clause uses statement word order: where + subject + verb.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
The question is whether we can finish today.
The whether-clause is a complement after be.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
I can't remember what she said.
What she said is the thing the speaker cannot remember.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
She said that the meeting was short.
The that-clause reports the content of what she said.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
My concern is that we are moving too fast.
The that-clause explains the concern.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
Whether they agree depends on the price.
Fronted whether-clauses are common in careful or formal style.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
I'm not sure if the door is locked.
The if-clause completes the adjective sure.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
That he apologized surprised everyone.
The whole that-clause is the subject of surprised.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
It surprised everyone that he apologized.
This is the smoother everyday version of a long subject clause.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
Where did Ana put the keys?
This is a direct question, so it uses question word order with did.
I know where Ana put the keys.
The embedded noun clause does not use did or question inversion.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
Is the train late?
This is a direct yes/no question with be before the subject.
Do you know if the train is late?
The main sentence is a question, but the noun clause is the train is late.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
I heard that Sam hired a new assistant.
This that-clause works as a noun clause, the object of heard.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
I met the woman that Sam hired.
This is a relative clause, not a noun clause, because it describes woman.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
I asked where was the file.
Do not keep direct-question inversion inside a noun clause.
I asked where the file was.
The embedded question is a noun clause with statement word order.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
We discussed if to postpone the trip.
Use whether to, not if to, before an infinitive choice.
We discussed whether to postpone the trip.
Whether can introduce an infinitive choice; if cannot in this frame.
Lies den Satz in Sinneinheiten, nicht Wort für Wort.
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