become ill BrE
fall ill BrE
get sick AmE *
be taken ill
be taken sick
fall sick

They had fallen sick for far longer than the others.

Perhaps not, but he might fall sick, slow her up.

What will happen to the business if you fall sick or die?

No one can ever be sure that he or she might not suddenly fall sick.

We should've known better, but the men began to fall sick.

One day I fell sick in the middle of the road.

At the end of the 1990s his mother fell sick with cancer.

We'll have that over with before any of us fall sick.

A few days ago one of the inside men fell sick.

Then she fell sick and died in a matter of days.