我仰卧睡觉，但总是以不同的姿势醒来。

I go to sleep on my back but I always wake up in a different ___position.

保持瓶子直立。

Keep the bottles in an upright ___position.

长时间以不舒服的姿势坐着会导致背痛。

Sitting in an uncomfortable ___position for a long time can cause back pain.