除非他亲口对我说，否则我决不相信。

I will not believe it unless and until he tells me so.

Source: Tatoeba

Sentence Composition

1 除非 chúfēi
  1. only if (..., or otherwise, ...)
  2. only when
  3. only in the case that
  4. unless
2 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)
3 亲口 qīnkǒu
  1. one's own mouth
  2. fig. in one's own words
  3. to say sth personally
4 对 duì
  1. right; correct
  2. towards; at; for
  3. concerning; regarding
  4. to treat (sb a certain way)
  5. to face
  6. (bound form) opposite; facing; matching
  7. to match together; to adjust
  8. to fit; to suit
  9. to answer; to reply
  10. to add; to pour in (a fluid)
  11. to check; to compare
  12. classifier: couple; pair
5 我说 wǒshuō
  1. I wondered that and now it makes sense that...
  2. Used other than figuratively or idiomatically: see 我, 說 /说.
6 否则 fǒuzé otherwise; if not; or (else)
7 我 wǒ
  1. I
  2. me
  3. my
8 决不 juébù
  1. not at all
  2. simply (can) not
9 相信 xiāngxìn to believe; to be convinced; to accept as true