他的死因仍然是一個謎。

The cause of his death still remains a mystery.

Source: Tatoeba

Sentence Composition

1 他 tā
  1. (third-person singular) (since the early 20th century, usu. male) he; him; his
  2. (bound form) other; another; some other (as in 他日 tārì and 他人 tārén)
=2 的 de
  1. of; ~'s (possessive particle)
  2. (used after an attribute when it modifies a noun)
  3. (used at the end of a declarative sentence for emphasis)
  4. (used after a noun, verb or adjective to form a nominal expression, as in 皮革的 pígéde "one made of leather" or 跑堂儿的 pǎotángrde "a waiter (literally, one who runs back and forth in a restaurant)" or 新的 xīnde "new one")
  5. also pr. dì or di in poetry and songs
=2 的 dī a taxi; a cab (abbr. for 的士 dīshì)
=2 的 dí really and truly
=2 的 dì (bound form) bull's-eye; target
3 死因 sǐyīn cause of death
4 仍然 réngrán still; as before; yet
=5 是 shì
  1. to be (followed by substantives only)
  2. correct; right; true
  3. (respectful acknowledgement of a command) very well
  4. (adverb for emphatic assertion)
=5 是 shì variant of 是 shì
=6 一個 yīge
  1. a; an; one
  2. the whole (afternoon, summer vacation etc)
=6 一個 yīgè
  1. Combination of the numeral 一 (“one”) and the generic classifier 個／个: a; an; one
  2. same
=7 謎 mèi see 谜儿 mèir, riddle
=7 謎 mí riddle