Usage of know

[daemon99]

have a question on the usage of the word know. Please have a look at the sentence below.

1) He will kill her when he knows that she has been cheating on him.

Is the usage of know in the above sentence correct?

Are the following sentences OK?

2) He will kill her when he gets to know that she has been cheating on him.
3) He will kill her when he comes to know that she has been cheating on him.

[Raymott]

have a question on the usage of the word know. Please have a look at the sentence below.

1) He will kill her when he knows that she has been cheating on him.

Is the usage of know in the above sentence correct?

Are the following sentences OK?

2) He will kill her when he gets to know that she has been cheating on him.
3) He will kill her when he comes to know that she has been cheating on him.

These all sound strange. The most often phrasing is:
"He will kill her when he finds out that she has been cheating on him."
We don't use "come/get to know". Use "to find out" or "to discover".