Question

I don't know when he Departed turn into a simple sentence​

Answer 1

Rewriting the given sentence into simple sentence form is as follows:-

His departure was unknown to me.

• sentences are of three types - simple, compound and complex.
• a simple sentence has only one independent clause.
• a compound sentence is formed of two independent clauses joined by a coordinating conjunction.
• a complex sentence is formed of an independent clause and a dependent clause, joined by a subordinate conjunction.
• in the given sentence, when is a subordinate conjunction, which when removed we form an independent clause from the given two seperate clauses to get a simple sentence.