"Two animals are standing there."
In Japanese, you also have the option of placing the number and counter before the noun, but this is less common and typically involves an additional particle.
[Number + counter] の [Noun + particle] always works. [Noun + particle] [Number + counter] works if the particle is は, が, or を. There's also a different shade of meaning. If the number comes first, you're talking about specific/definite things, but if it comes after, it's general/indefinite. So えんぴつを二本ください means I want any two pencils, but 二本のえんぴつをください means I want two specific pencils. In English it would be the difference between "Please give me two pencils" vs. "Please give me the two pencils."
There are a few exceptions - if you know these, you should be able to apply them to bigger numbers. Numbers ending with "chi", "ku" and "n" are the offenders in this scenario (and number 10).
1 animal is "ippiki" (ichi + hiki becomes ippiki) 3 animals are "sanbiki" 6 animals are "roppiki" (roku + hiki becomes roppiki) 8 animals are "happiki" (hachi + hiki) 10 animals are "jupikki" (juu + hiki)
And greater numbers than that follow the same pattern.
If you ask "how many animals", it would also be "nan biki", just like the h turns into b with 3 animals.
Hope that makes sense!
The pronunciation changes based on the sound that comes before the counter to ease pronunciation. 十二匹 is じゅうにひき。
Actually this might not be entirely true, but the rules around when counters can come after nouns seem a bit odd, especially as far as when this course considers them acceptable answers. But placing the counter directly after the noun, even if grammatically acceptable, it relatively unusual from what I've observed.