How To Use "Had" Properly? Can You Give Me Some Tips On Sentence Making?

"Had" is the past tense of the verb "have." It is also the past participle, ie the third form. Mostly "had" is used in past sentences like these:

-I had a letter; I had a headache; I had breakfast; I had a shower.

You can see that the meaning is a little different in each case (received; suffered from; ate; took.) "Have" is a very general verb with a lot of uses, but the sentences are quite simple. Remember that the question form is "Did you have (a letter)?" and the negative is "didn't have."

"Had" is also used in sentences like these:

-I've just had my breakfast
-I haven't had a letter yet.
-I had already had a shower when he arrived.

It looks confusing, but the thing is to remember that "had" is both a full verb and an auxiliary (extra or "helping") verb. In "i have had" or "I had had" the first verb is just an extra, while the second one actually has meaning. So you could say "I have eaten" or "I had eaten" (instead of "I had had") and the grammar would be the same.

How To Use "had had" Properly? Can You Give Me Some Tips On Sentence Making?