She is going to spend her vacation in Hawaii.
Does it mean that the speaker knows for sure that she has decided to go Hawaii ? OR does it mean that the speaker just guesses or speculates that ?
English Language Learners Stack Exchange is a question and answer site for speakers of other languages learning English. It only takes a minute to sign up.
Sign up to join this communityShe is going to spend her vacation in Hawaii.
Does it mean that the speaker knows for sure that she has decided to go Hawaii ? OR does it mean that the speaker just guesses or speculates that ?
She is going to spend her vacation in Hawaii.
There are two possible interpretations of this sentence according to grammar books.
Put simply, she has made the decision — in the past — to travel and spend her vacation in Hawaii
Prediction
The person is about to spend her vacation on the Hawaiian islands. We base our prediction on something that can be seen, and therefore deduced. We might see the person in an airport with her boarding card, maybe she and her partner are wearing typical Hawaiian-style shirts. Or maybe she is actually boarding a Hawaiian Airline airbus which is scheduled to take off.
Usually a sentence similar to the OP's refers to the first meaning, but without context we can never be 100% certain.
Advanced Language Practice by Michael Vince
Unit 2 Tense Consolidation: future time
3. Be going to describes intentions or plans. At the moment of speaking the plans have already been made.
I'm going to wait here until Carol gets back
Going to is also used to describe an event whose cause is present or evident.
Look at that tree! It's going to fall.
Decisions expressed with going to refer to a more distant point in the future.
A Practical English Grammar Fourth Edition, by A.J.Thomson, A.V.Martinet
206 The be going to form used for prediction
A The be going to form can express the speaker's feeling of certainty. The time is usually not mentioned, but the action is expected to happen in the near or immediate future [...]
B 1
be going to implies that there are signs that something will happen
Yes. It seems that the speaker knows it as a fact. Else, it could have been said that "she may be going to".
Allwords.com defines "going to" as:
Going to - verb
"Going is the present participle of "to go" and "to," in this case, denotes an inifnitive. "Going to" is technically a progressive participle, in which "going" serves as an auxillary verb, and is always preceded by the verb to be or a conjugation thereof. It is, however, almost always used as form of the future tense: I am do do, I will do, I shall do); or as the past progressive(imperfect) to indicate definite non-completion: "I was do" as as opposed to "I was doing."
I have also taken definitions and examples from dictionary.com which goes as:
going to
About to, will, as in I'm going to start planting now, or Do you think it's going to rain? or We Thought the train was going to stop here. This Phrase is used with a verb ( start, rain, stop in the examples) to show the future tense.Occasionally the verb is omitted because it is understood. For example, That wood hasn't dried out yet but it's going to soon, or Will you set the table?—Yes, I'm going to"
But in this example it is pretty clear the the action is about to happen in the future for sure.