present continuous for a temporary habit

Question

1. So now David is studying in the USA he is not coming back very often
2. So now David is studying in the USA he won't come back very often
3. So now David is studying in the USA he does not come very often

So what is the best solution : Is it "he is not coming back"? I think it is the best since studying in the USA is very recent, so it is a very new changement which will last only two or three years but may be present will be ok too because present continuous is already used for study so may be it is not obligatory to use present continuous for come

Answer 1

It would be much clearer that the statement is a temporary situation if you used the while preposition:

• While David is studying in the USA he will not come back very often.
• While David is studying in the USA he won't come back very often

'While' shows that the situation is expected to come to an end.

Alternatively, you could use since to mark the beginning of the period. As most people will recognise that 'studying' does not last forever, it should be a given that it will end.

• Since David began studying in the USA he hasn't come back very often

The difference here is that there is no inference you expect him to come back more often once the study has completed.

Answer 2

All of those sentences are grammatical.

With the adverb very often they also all make sense. (Somehow, when I first answered this, I had missed those words and answered differently.)

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If you are stressing that this is a very recent thing (let's say that he only moved to the U.S. a week ago), and he has yet to come back at all, then you're right that there hasn't been a pattern of habituation. Therefore, the future tense version would sound more natural:

Now that David is studying in the U.S., he won't come back very often.

Or, alternatively:

Now that David is studying in the U.S., he isn't going to come back very often.

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Note that this makes a lot more sense if David had been living somewhere else in his home country and coming back is referring to visiting his family home. (And assuming that he used to come back home often before he left the country.)

If this is actually a statement about his leaving the country that's causing him to be away from home in the first place, then it would be more natural to say:

Because David is studying in the U.S., he (won't / isn't going to) come back very often.

Answer 3

1) So now David is studying in the US, he isn't coming back very often. [these days, at present]

2) So now David is studying in the US, he won't come back very often. [future, come back in the future as a general proposition.]

4) So now David is studying in the US, he won't be coming back very often. [future, repeatedly coming back in the future]

One way to look at this is to compare it to simple present and present continuous: won't be coming back is to won't come back very often

as isn't coming back [at the moment or as a future] ] is to doesn't come back [a general statement]

The future continuous is for a future ongoing or continuous activity.

I'm eating a lot of bread these days.

I won't be eating a lot of bread this summer.

I eat a lot of bread now. [general statement].

I won't eat a lot of bread very soon. [in the future, often, an intention, general future statement]