读下面对话，回答3-6题:
A: You’ve been yawning all day. Are you OK?B: Yeah. I’m just feeling tired.A: How much sleep did you get last night?B: About five hours, I guess.A: That’s not enough. I heard we need about seven to nine hours of sleep every night.B: Yeah, I usually get more sleep. It’s just that I’ve been stressed out over schoolwork recently.A: Maybe you should find a way to cope with the stress so you can get more rest. How about doing some exercise?B: I’m not really into sports. I prefer activities like reading.A: Reading is good, too. As long as it’s something you enjoy, it will help reduce your stress.选出升降调标注正确的句子：