CEFR B1; focus: must and have to for obligation.
Exercises
Can and Can’t Exercise
A1 practice with can and can’t for ability, permission, and present possibility.
Adjective to Noun Conversion Exercise
CEFR B2 ยท Adjective to noun conversion
Register-Preserving Paraphrase Exercise
C2 register-preserving paraphrase; each item has one objectively licensed answer.
Giving Personal Advice Exercise
B1 ESL multiple-choice gap-fill exercise on giving personal advice.