Page 222 - Practical English Usage 3ed - Michael Swan, Oxford

2 present progressive and going to ... : differences
In many cases, both structures can be used to express the same idea.
I'm washing I going to wash my hair this evening.
But there are some differences. For example, we prefer going to ... when we are talking not about fixed arrangements, but about intentions and decisions. Compare:
- I'm seeing Phil tonight. (emphasis on arrangement)
I'm really going to tell him what I think ofhim. (emphasis on intention: NOT Pm rettUy teEling him . ..)
- Who's cooking lunch? (asking what has been arranged) Who's going to cook lunch? (asking for a decision)
Because the present progressive is used especially for personal arrangements, it is not generally used to make predictions about events that are outside people's control.
It's going to snow before long. (NOT It's srwwing before [(mg.)
1can see that things are going to get better soon. (NOT ••• things are getting
bene" S6BIi.)
And the present progressive is used for actions and events, but not usually for permanent states. Compare:
Our house is getting I is going to get new windows this winter.
Their new house is going to look over the river. (NOT Thei" new hBttSe is
16B/eing Bve" me ";IJ€I'.)
3 commands and refusals
The present progressive can be used to insist that people do things or do not do things.
You're finishing that soup ifyou sit there all afternoon! She's taking that medicine whether she likes it or not!
You're not wearing that skirt to schooL
The present progressive is common in emphatic refusals.
I'm sorry, you're not taking my car. I'm not washing your socks - forget it!
For a comparison with lVill. see 216.
215 future (5): simple present
1 timetables etc: The summer term starts . ..
We can sometimes use the simple present to talk about the future. This is common when we are talking about events which are part of a timetable, a regular schedule or something similar.
The summer term starts on April 10th. What time does the bus arrilJe in Seattle? My plane leaves at three o'clock.
Are you on duty next weekend? The sun rises at 6.13 tomorrow.
Will is also usually possible in these cases.
future (5): simple present 215
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