To cross swords

I am afraid the two brothers are <u><em>at cross purposes</em></u>.

Be in the mire

He visits the doctor <u><em>off and on</em></u>.

To give a false colouring

Leaders should not only make speeches, they should also be prepared <u><em>to bell the cat</em></u&…

The class could not <u><em>keep a straight face</em></u> on hearing the strange pronunciation of…

I <u><em>raked my brains</em></u> to solve this difficult problem.

His biographers discovered to their surprise that he was an atheist <u><em>to the backbone</em></u&…