[Noun Clauses] Noun clauses that begin with if (Provided) or whether

 

I don’t know whether she will come. I don’t know if she will come.
I wonder whether he needs help.  I wonder if he needs help.	Whether is more common than if in formal English.
I wonder whether or not she will come.
I wonder whether she will come or not.
I wonder if she will come or not.
Whether she comes or not is unimportant to me.	Noun clause is in the subject position.

 

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Do you still have Yung Soo's address?

I don't know if I still have Yung Soo's address.

Provided (that) [連接詞] 倘若…；以...為條件；假如…，為假設語氣的句型。 Provided that everybody finishes summer homework in time, we’ll go to Taitung for this year’s family trip.