'Has had' and 'Had had'

Students often ask me when to use 'has/have had' and 'had had' constructions. The answer is really quite simple - both of these are nothing but the present perfect and past perfect forms of the verb 'to have'.

• Has/Have had - Present perfect of 'to have'
  
  
• Had had - Past perfect of 'to have'

Consider the following sentence as an example:

- John travels to many different countries.

The verb in the above sentence is 'travels' which is in the simple present tense. Now if we were to convert this sentence into the Present perfect tense (which basically signifies an action that started in the past and continues into the present), we need to add 'has/have' followed by the past participle form of the verb (in most cases just add the words '-ed' to the verb, like 'traveled' in the above sentence).

The final sentence would read something like this:

- John has traveled to many different countries.

Similarly to convert this same sentence into the Past perfect tense (two actions happening in the past - the earlier action takes the past perfect and the latter action takes the simple past tense), we need to add 'had' followed by the past participle form of the verb.

The final sentence would read something like this:

- John had traveled to many different countries before he decided to settle down in New Zealand.

Sounds fairly simple, but the problem starts when the verb in question happens to be 'to have/has' instead of say 'travels' in the above example.

For example, consider the following sentence:

Tim has several passenger cars.

The verb in the above sentence is 'has' and it is in the simple present tense. Now to convert this into the present perfect tense apply the rule as discussed above - 'has' followed by the past participle of 'has' which is 'had'. The final sentence reads:

Tim has had several passenger cars.

Similarly the past perfect tense will read - 'had'

followed by the past participle of 'has', so you get:

Tim had had several passenger cars before he decided to buy a sports car.

So 2 things happening the past - Tim had several passenger cars first, which takes the past perfect tense with the extra 'had and he 'decided' (simple past tense) to buy a sports car later.

To Sum it up:

• 'Has/have had' and 'Had had' are present perfect and past perfect forms of the verb 'to have'.
  
  
• To convert a sentence into the Present perfect tense - Add 'Has/have' + past participle form of the verb (usually add '-ed')
  
  
• To convert a sentence into the Past perfect tense - Add 'Had' + past participle form of the verb (usually add '-ed')