1. A Tough Nut to Crack

2. 10 He's a tough nut to crack.

3. 27 The final exam was a tough nut.

4. 5 It is a tough nut for him to crack.

5. A Bitter pill to swallow+a can of worms+a hard / tough nut+ a pint of Bitter a time of heady prosperity, Bitter partisanship, cultural frivolity and excess and