1. He is a great swimmer. He _______ swim across this river. can should might 2. _______ I borrow your pen for a moment, please? Must May Should 3. You _______ see a doctor. That cough sounds serious. should can may 4. It's a strict rule. All visitors _______ report to the reception. could must might 5. Take an umbrella. It _______ rain later today. can might should 6. When I was a child, I _______ climb trees easily. can could may ...