I can say:

By that time, I will have taken ten tests.

I want to know, can I in Present Perfect substitute will with be going to?

By that time, I am going to have taken ten tests.

3 Answers 3


There is nothing to prohibit this construction, and if you use it it will neither raise eyebrows nor be misunderstood. Here are a couple of examples:

A lot of people graduating with an MPH are going to have taken the same classes, so you'll have an advantage if you can show that you have been responsible for data analysis. — Beth Seltzer, 101 Careers in Public Health, 2010

And if, like Nick, you were in the front line and not merely a blanket stacker stuck back at base, then of course it's going to have taken its toll. —Jan Evans, A Maid of Kent: A Novel Set Against the Backdrop of the Falklands War, 2011

But this is a very rare usage. Outside of formal texts on linguistics, those are the only two instances of "going to have taken" actually reported by Google Books.

If you run across it, you will know what it means; but there is no need to incorporate it in your working vocabulary.


The "be going to do something" construction is similar to "will do something" for the future tense, and thus they both can be used with non-perfect (to do) and perfect (to have done) infinitives.

For example, the sentences

By next June I will have gone to Spain


By next June I am going to have gone to Spain

will express the same idea. So they may be regarded as interchangeable, and if there is any difference between them, it would lie solely in choosing between "I will" and "I am going to", depending on the reasons you have in mind in favor of either the former or the latter.

At the same time, you should bear in mind that "will have finished" is undoubtedly more economical and smooth, so it's up to you to decide whether there's any profit in using the longer version.

In my opinion, similar to that of @StoneyB's, simply knowing that such a construction is grammatically valid and recognizing it in texts (should you come upon it again), would be just about enough for an advanced ESL learner.


When you use the future perfect tense, you use 'will' only, and not 'be going to'. That is a grammatical rule, so no further explanation is necessary.

  • 1
    I think this answer is going to be downvoted.
    – Jim
    Commented Jun 22, 2013 at 16:09

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