Detecting the eclipse on it would be a formidable problem.

Any attack on Beaumaris would have been presented with formidable problems.

Once confirmed, the new board will face formidable problems.

Any novelist who writes about violence against women faces three formidable problems.

That should not be a formidable problem, but on environmental matters, nothing in this Congress comes easily.

That wealthy candidates can buy political offices is a formidable problem.

It's as though we had counted on Soviet power to keep these formidable problems under control forever.

The lack of material and human resources proved to be a formidable problem.

Spain emerged from the civil war with formidable economic problems.

It is a formidable problem, not just in this connection, as well we know.