Mr.Maru: Hey sparky, what are you going to do this weekend.
Sparky: I don't know. I think I'm going to eat large amounts of bacon.
Mr.Maru: Where are you going to get this bacon?
Sparky: You are going to buy it of course.
Mr.Maru: I don't think so.
Sparky: I guess the newspaper is not going to be in one piece then. And you can forget about your shoes.
Mr.Maru: All right, I'll buy you bacon.

What are the differences between 'be going to' and 'will'?  When do we use will?  When do we use 'be going to'?  There are a few basic guidelines for each.

be going to - basic usage

We can use 'be going to' for plans for the future.  These are plans that were made in the past before now.  These is especially used in informal situations.  For example,

I'm going to go fishing this weekend.  ( I have made the plans to go fishing this weekend.)
The meeting is going to be on Tuesday.  (Somebody planned the meeting to be on Tuesday.)
The family is going to go to Florida for summer vacation.  (The family has made the plans to go to Florida for summer vacation.)

We can also use 'be going to' for things that are on the way.

She's going to graduate in July.  (She may or may not want to graduate, but it is coming in July.)
It's going to snow tonight.  (The snow is coming.  You may or may not have planned for the snow.)

will - basic usage

We also use 'will' to talk about the future in a slightly different way.  We often use 'will' for predictions.  For example,

I think Spain will win the World Cup.

It'll be cold tomorrow.
This test will be easy.

We also often use 'will' when we make a decision about a future activity at that time.  We haven't planned it before now.  For example,

A: I'm going to the store.  Do you want to come?
B: Sure.  I'll come.

A: We have some extra cake.
B: I'll eat it.

be going to vs. will

For predictions, we can use will if we only have internal evidence.  We usually use 'be going to' if there is external evidence.  For example,

I'm going to fail this test.  My teacher told me I need to study more.
I'll fail this test.  I haven't studied a lot.

I went to the travel agency.  It's going to cost $1000 to fly home.
I think it'll cost about $1000 to fly home.

For other situations, you have to think about the intention or what the speaker wants to do.  For example,

I'm going to the store.  (I want to go to the store.)
I'll go to the store.  (I'm thinking about going to the store.  Somebody might stop me though.)

Be careful!  This difference is not very important.  Both 'be going to' and 'will' can be used.

Do you think you understand?  Let's take a short quiz.

1) I think I _____ go for a walk.  It's a nice day.

A) will
B) am going to

2) Jenny and I ________ go swimming this weekend.

A) will
B) are going to

3) This weekend, it ___________ be partly cloudy with a chance of thunderstorms.

A) wil
B) is going to

Answers

1) A) - 'will' is the best answer because the speaker did not have the intention.  He decided at that moment.
2) B) - 'be going to' is the best answer because it sounds like a plan for this weekend.
3) A) - 'will' is the best answer because we are making a prediction or guess about the future.  We do not have any strong outside evidence.

Thanks for stopping by this week.  I hope everyone enjoyed the World Cup.  If you have a question about grammar, please email me at This e-mail address is being protected from spambots. You need JavaScript enabled to view it .