GMAT Verbal Section | Re: Present tense and present perfect - impossible?

It's possible! There's no rule against combining different tenses in the same sentence,as long as the sentence makes logical sense that way .

For instance, this is a logical sentence:

I bought a gallon of milk and will drink it this week.
And this is an illogical sentence:

I drank a gallon of milk and will buy it this week.
You could construct both logical and illogical sentences
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