偶数乘以奇数是偶数，奇数乘以奇数是奇数。

Even times odd is even, odd times odd is odd.

Source: Tatoeba

Sentence Composition

1 偶数 ǒushù even number
2 乘以 chéngyǐ (math.) multiplied with
3 奇数 jīshù odd number
=4 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)
=4 是 shì variant of 是 shì
5 偶数 ǒushù even number
6 奇数 jīshù odd number
7 乘以 chéngyǐ (math.) multiplied with
8 奇数 jīshù odd number
=9 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)
=9 是 shì variant of 是 shì
10 奇数 jīshù odd number