我该去睡觉了。

I have to go to sleep.

I have to go to bed.

Source: Tatoeba

Sentence Composition

1 我 wǒ
  1. I
  2. me
  3. my
2 该 gāi
  1. should
  2. ought to
  3. probably
  4. must be
  5. to deserve
  6. to owe
  7. to be sb's turn to do sth
  8. that
  9. the above-mentioned
3 去 qù
  1. to go
  2. to go to (a place)
  3. (of a time etc) last
  4. just passed
  5. to send
  6. to remove
  7. to get rid of
  8. to reduce
  9. to be apart from in space or time
  10. to die (euphemism)
  11. to play (a part)
  12. (when used either before or after a verb) to go in order to do sth
  13. (after a verb of motion indicates movement away from the speaker)
  14. (used after certain verbs to indicate detachment or separation)
=4 睡觉 shuìjiào
  1. to go to bed
  2. to sleep
=4 睡觉 shuìjué
  1. (archaic, intransitive) to wake up
  2. to wake up
=5 了 le
  1. (completed action marker)
  2. (modal particle indicating change of state, situation now)
  3. (modal particle intensifying preceding clause)
=5 了 liǎo
  1. to finish
  2. (used with 得 dé or 不 bù after a verb to express (im)possibility, as in 忘不了 wàngbuliǎo "cannot forget")
  3. (literary) (usually followed by a negative such as 无 wú or 不 bù) completely (not); entirely (not); (not) in the least
  4. to understand clearly (variant of 了 liǎo)
=5 了 liǎo
  1. (of eyes) bright
  2. clear-sighted
  3. to understand clearly
=5 了 liào unofficial variant of 瞭 liào