01 My grandfather used to run a pharmacy here.
02 You had better not walk alone at night. It's very dangerous.
03 You ought to have called my home before you went there.
04 The examination could not have been more difficult.
05 The weather is warmer than it ought to be for this time of year.
06 You might have discovered these five countries do business differently.
07 Kenji must have done extremely well in his exams because he got into the top university in his area.
★ 05 がやや難問だと思いました。