Ответ:

1 In the stage of **light** sleep we can wake up easily, whereas if we are deeply asleep it's more difficult to wake up.

2 When we sleep, our body **temperature** drops, which is why we often feel sleepy when we're cold.

3 Dreaming helps us to sort through information and **solve** problems.

4 Breathing, digestion and other natural **bodily** functions.

5 Sleep isn't just a(n) **resting** state- our brains actually remain very active when we're asleep.

6 Our bodies **repair** cells when we are sleeping, so it's important to get enough rest.

7 Annie doesn't have a very strong **immune** system, which is why she is always getting sick.

8 When we run fast, our **heart** rate increases.

Буду вдячний за позначку "найкраща відповідь "