- future / prediction → Anna will come tomorrow around 5:00.(4.1-2)
- willingness – a decision made by a speaker at the moment of speaking → The phone is ringing. I'll get it.
- refusal → She won't take her medicine. (animate); The car won't start. (inanimate)
Be going — expresses a prior plan (a plan made before the moment of speaking). I'm going to paint my bedroom [plan already in action]
English lacks a future tense. The future (Futurity) is expressed with modals, especialy will, or semi-modal expressions such as be going (to). (3 §10.1)
The non-progressive aspect suggests a schedule or plan. The progressive aspect suggests the plan is in action. I'll phone her tonight. / I'm phoning her tonight. I'm going to phone her tonight. (3 §8.3)
Will expresses (3 §9.5)
- futurity → He will be two tomorrow. [fact]
- futurity (epistemic) → He will be tired tomorrow. [prediction (opinion)]
- assumption or expectation (epistemic) → You can look it up. It will be in the dictionary.
- volition "willingness" (dynamic) → I will be back at 2:00. (shall) / He won't help us. (3 §9.5.2)
- propensity → Oil and vinegar will separate. (tendency; behavior or properties of inanimate)
Be going is informal. "Be" has the full set of inflectional forms.
- Be going focuses on matrix time – speaking of future as it relates to present plans; activity partially in motion → I'm going to retire in ten years.
- Was going (past) Unlike is going, was going does not entail that the complement situation was actualized. He was going to ask you. (3 §10.2.7)
- intention vs. willingness → I've asked her to help, but she's not going to. (intention) I've asked her to help, but she won't. (refusal)
Will expresses (629)
- future auxiliary → I will be happy when this is done.
- certainty or confidence about a future situation → It will cost a lot to fix that.(629.3)
- information and prediction It will be cold tonight. (212)
- willingness and decisions → Who can help? I will. / I will stop smoking.
- requests, orders and offers → Will you be quiet? What will you drink? Students will do weekly homework.
- typical behavior → Boys will be boys.
- refusal (negative) → The car won't start. The donkey won't move. (217.4)
Be going expresses (213)
- plans that have some present reality→ I'm seeing Janet on Tuesday. [current intentions]
- predictions with "outside evidence" → See those clouds? it's going to rain. [present evidence] "I can see them coming."
- refusals → I'm not going to take this anymore. (213.4)
Will / Be going (Biber 6.6.0-6.6.4)
There is no formal future tense in English. (18.104.22.168)
Modals and semi-modals can be grouped into three categories: (485)
- permission/ possibility / ability: can, could, may, might
- obligation / necessity: must, should, had better, have (got) to, need to ought to, be supposed to
- volition / prediction: will, would, shall, be going to
Semi-modals → be going (to), ought (to), have (to), need (to), had better, have got (to), be supposed (to)
Each modal can have two types of meaning:
- intrinsic: actions and events that humans (or other agents) control directly: permission, obligation, volition (or intention)
- extrinsic: logical status of events or states; assessments of likelihood: possibility, necessity, or prediction