Help with phrase

Hi,

Can you please help me complete the following phrases:
1. As weak as ....
2. As agile as ....

Is it water for the first and monkey for the second?

For the first phrase, "as weak as water" and "as weak as a kitten" are both conventional. If you're completing a school assignment, I suppose the conventional answer is what's wanted. In original writing, it's best to think up one's own comparisons.