both 'has had' and 'have had' denote present perfect tense (linking the past and the present actions) while 'had had' denotes past perfect tense (connecting two actions in the past itself). Now to the examples: I have had (eaten) my breakfast but I have not yet had (drunk) my coffee.
Also know, when to use have had and has?
In the present tense, "have" is used for I, you, we, and they and all plural nouns. "Has" is used for he, she, and it, and for all singular nouns. ("Has" is the third person singular form of "have.") In the past tense, "had" is used for everything.
Has have had difference?
1. 'Has' is the third person singular present tense of 'have' while 'had' is the third person singular past tense and past participle of 'have. ' Both are transitive verbs, but 'has' is used in sentences that talk about the present while 'had' is used in sentences that talk about the past.
What is have had in grammar?
The past perfect form of have is had had (had + past participle form of have). The past perfect tense is used when we are talking about the past and want to refer back to an earlier past time. They dismissed him before he had had a chance to apologize.
Has or had grammar?
Has is the simple present tense (3rd person singular) form of the verb to have. We use it when we conjugate the verb for he/she/it, a named person, or other singular nouns. For example: I have, you have, he/she/it has, we have, you (plural) have, they have. Had is the past tense form of the verb to have.