will vs going to

		less < CERTAIN		more > POSSIBLE
		WILL	= / <>	GOING TO
Short term	PREDICTIONS	< probable	DIFF	> possible
		It __will rain__ (rain) tomorrow.		Look! The clouds are black! It __is going to rain___ (rain) in a moment.
				Look! She __ is going to have__ (have) a baby.
	PLANS	a sudden decision	DIFF	a plan already made
		H: I don’t have sugar. L: I __will buy___ (buy) some, mom.		A: Where are you going to go, Loanna? L: I __am going to buy__ (buy) sugar for mom.
Long term	PREDICTIONS	< probable	SAME	> probable
		You will be very successful. (in many years, not immediately) You are going to be very successful. (in many years, not immediately)
	PLANS	< probable	SAME	> probable
		I will graduate from college in 5 years. (Not immediately) I am going to graduate from college in 5 years. (Not immediately)