Question

I have found the book. I had lost it. (into complex sentence)

Answer 1

Answer:

The given sentences can be changed into a complex sentence as shown below:

I have found the book that I had lost.

or

I have found the book which had been lost.

Explanation:

A complex sentence has one independent and one or more dependent clauses. The clauses in a complex sentence can be in any order. If the dependent clause is first,  a comma is usually after it.

Example

I hope that I will pass the test.

Answer 2

I have found the book that i had lost.

Explanation:

• The 'complex sentence' is a sentence' having an 'independent clause and at least 'one dependent clause'.
• An independent clause gives a complete thought while a 'dependent clause' is depends on independent clause. A clause has both the subject and verb.  

For example:

• Although she had some doubts, she found the book very useful.
• I burnt the chicken, but not the cake.

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