Questions with / without a subject

QUESTIONS WITH AND WITHOUT AUXILIARIES:

WITH SUBJECT WITH AUXILIARY	NO SUBJECT NO AUXILIARY	TRANSLATION into Spanish
Who did you phone? Who did you speak to? Who did you help? Who did you write to?	Who phoned? /  Who phoned you? Who spoke? /  Who spoke to you? Who helped? / Who helped you? Who wrote? /  Who wrote you? Who sang in the concert?	¿Quién llamó?/  ¿Quién te llamó? ¿Quién habló?/ ¿Quién te habló? … …
------------------------ What did you drop?	What happened (to you)? What fell on the floor?	¿Qué se te cayó? ¿Qué se cayó al suelo?
	Which actor won the Oscar? Which countries are in war? Which CD won the award?
	How many writers won the Nobel prize this year? How many people had an accident this year?

EXPLANATION:

When we don’t know the subject (who or what) did the action, we ask about it and then, we don’t need to use the auxiliary verb. Auxiliary verbs are used in negative and in questions to invert the order of the sentence. Eg.:

-I don’t write letters.

-Do you write letters? / Do you usually write letters?

-Who did you write to?

-Who wrote you (a letter)? NO AUXILIARY VERB because we don’t know the subject.

I hope now you understand better. Good luck!