Help with my grammar! ING form after comma! :S?

Question

Can you explain the ing verbal form after comma? These are actions occurring exactly at the same time but in past tense, right?

Are they the same?

1) A wild boar, big as a small bear, approached us, grinding his s*x inch lower tusks against his shorter upper tusks to keep them from getting too long.

2) We walked slowly, hearing only the scuff-scuff of our boots on the grassy slope.

Could I say: We walked, hearing...or we walked and heard?

Thanks in advance!

Answer 1

Generally speaking, we use ~ing after a comma for one of three reasons:

    
1. When two actions happen at the same time (eg: "He runs away and laughs" becomes "He runs away, laughing")

    
2. When the second action is a part of the first action (eg: "He leaves and locks the door" becomes "He leaves, locking the door") 

    
3. When the second action is a consequence of the first action (eg: "He rushes through the busy street and knocks an old lady over" becomes "He rushes through the busy street, knocking an old lady over")

Note that the key difference between 1 and 2 is that the verbs used in 1 aren't really related to one another (ie: you do not need to be running away to be laughing) while in 2 they are directly related to each other (ie: you would lock the door as you are leaving your house).  In 2 the actions happen at roughly the same time, but in 3 the second action happens after the first.

 

I think that your first example is similar to 1, as two different things are happening at the same time in each sentence.  Your second example is more similar to 2, as you are walking and listening to the sounds that your feet make at the same time (so if you weren't walking, you wouldn't hear anything).

 

To answer your questions:

Q. Could I say: We walked, hearing...?

A. Yes, you can, as 'slowly' is just an adjective, and as such having it there does not necessarily make the sentence any more or less correct.

"We walked, hearing only the scuff-scuff of our boots on the grassy slope."

Q. Could I say: we walked and heard?

A. Yes, you can say that too.

"We walked and heard only the scuff-scuff of our boots on the grassy slope."