run across & run into

[kirimaru]

Both of them have the same meaning "to meet accidentally " How can I distinguish them ? Please help me .

I have an example from a multiple choice exercise

This morning I run .......Tom ,an old friend on my way to school .
A. into B. across

I do not know which to choose because I cannot distinguish them

[susiedqq]

This morning I ran into Tom ,an old friend on my way to school . (means that you met unexpectedly)

I ran across the information while looking for a recipe. (means to find something, discovered)

[banderas]

Both of them have the same meaning "to meet accidentally " How can I distinguish them ? Please help me .

I have an example from a multiple choice exercise

This morning I run .......Tom ,an old friend on my way to school .
A. into B. across

I do not know which to choose because I cannot distinguish them

susiedqq's disticntion is perfect but let me expand a little bit on them.

run into sth=to reach a particular cost or amount, as a total:
The repairs will probably run into thousands of pounds.
run into sth
If you run into problems, you begin to experience them:
We ran into bad weather/debt/trouble.

[kirimaru]

This morning I ran into Tom ,an old friend on my way to school . (means that you met unexpectedly)

I ran across the information while looking for a recipe. (means to find something, discovered)

This is what I found in Collin Cobuild V3 :
If you run across someone or something, you meet them or find them unexpectedly.
We ran across some old friends in the village.
=come across

Why so ?

This makes me puzzled when using run into /across to indicate that I meet someone by chance .

[Anglika]

Both do mean that you mean them, usually by chance

Guess what! I ran across Josie walking down the High Street with a new boyfriend.
When I was at the meeting last week I ran into Don. I hadn't seen him for ages.

[kirimaru]

Both do mean that you mean them, usually by chance

so,how can I choose the right answer for the multi choice exercise above ?

[banderas]

so,how can I choose the right answer for the multi choice exercise above ?

Did you see such a test when you were given:
a. run across b. run into. c...... d..........
and only one answer was correct?

[kirimaru]

Did you see such a test when you were given:
a. run across b. run into. c...... d..........
and only one answer was correct?

yes ,and other two options are :
c.Against
d. to

I think c & d are not correct ,so I only mentioned a & b.

[banderas]

yes ,and other two options are :
c.Against
d. to

I think c & d are not correct ,so I only mentioned a & b.

What is the example sentence? Can you provide it, please?

[Anglika]

so,how can I choose the right answer for the multi choice exercise above ?

This morning I run .......Tom, an old friend, on my way to school .
A. into B. across

It should be "I ran into" or "I ran across".

Either will work. I would suggest that "into" is what is being asked for.