what is it?
A dass-clause with the Perfekt is a subordinate clause introduced by the conjunction dass in which the main verb appears in the Perfekt tense. Because dass is a subordinating conjunction, it sends all finite verbs to the end of the clause. In the Perfekt, that means the past participle comes first, followed immediately by the auxiliary (haben or sein) as the very last element. This construction is used whenever a speaker wants to report or comment on a past event inside a subordinate clause.
when to use it
Reporting what someone said or thinks about a past event. Verbs such as sagen, glauben, denken, wissen, and hören frequently introduce a dass-clause when the embedded event happened before the moment of speaking.
Expressing a reaction to something that has already happened. Phrases like Es ist schön, dass … or Ich freue mich, dass … take a Perfekt subordinate clause when the thing being reacted to is a completed action.
Any time the embedded action precedes the main clause action. If the event inside the dass-clause is finished and prior to the main verb's time frame, use the Perfekt rather than the present tense.
formation
In a main clause, the Perfekt follows V2 order: the auxiliary occupies the second position and the participle goes to the end. Inside a dass-clause, both the participle and the auxiliary move to the end. The fixed order at the end is: participle → auxiliary.
| clause type | word order | example |
|---|---|---|
| main clause | auxiliary (pos. 2) … participle (end) | Er hat das Buch gelesen. |
| dass-clause | … participle … auxiliary (end) | … dass er das Buch gelesen hat. |
The choice of auxiliary follows the same rules as in any Perfekt construction: haben for most verbs, sein for verbs of motion or change of state (e.g. kommen, gehen, fahren). The auxiliary is conjugated to agree with the subject of the dass-clause, not the main clause subject.
Pattern: [Main clause], dass [subject] [other elements] [participle] [auxiliary].
examples in context
common pitfalls
Keeping V2 order inside the dass-clause.
Learners sometimes treat the dass-clause like a main clause and place the auxiliary in second position: ❌ Ich glaube, dass er hat das Buch gelesen. This is incorrect. dass is a subordinating conjunction: it pushes the finite verb — including the auxiliary — to the very end. Correct: ✔ Ich glaube, dass er das Buch gelesen hat.
Reversing the participle–auxiliary order at the end.
Because the auxiliary comes second in a main clause, some learners carry that pattern to the end of the subordinate clause and write: ❌ Ich glaube, dass er das Buch hat gelesen. In a dass-clause the required order is always participle first, auxiliary last. Correct: ✔ Ich glaube, dass er das Buch gelesen hat.
Both errors produce word orders that sound natural in a main clause but are ungrammatical inside a subordinate clause. When in doubt, locate dass and make sure the auxiliary is the absolute last word before the full stop or comma.
Three sentences, graded here. Nothing is saved and no account is needed.
Meine Schwester hat mir erzählt, dass die Kinder über den Witz ___ ___.
Fill in the blank with the correct Perfekt form of the verb in parentheses to complete the dass-clause. (lachen)