ate, eight, 8

Ate or ate is the past tense ( yesterday, or some time ago ) of "eat"--
There is pizza in the refrigerator. We only ate half of it yesterday.
We ate lunch in the cafeteria.

Eight or eight ( rhymes with ate ) means the number 8--
There are eight slices of pizza.  We can each have two.
Mom said to be home by eight o'clock.
There are twelve questions. We have to get eight of them right to pass.

Now that you know that, you can say--
"We ate dinner at eight o'clock.

Note--If you hear someone pronounce "ate" as "et" ( rhymes with get ), he or she is  British. In America  "ate"  rhymes with "eight".