Answer:
Step-by-step explanation:
The term cumbersome is defined as "large or heavy and therefore difficult to carry or use". This is fitting for the first blank as the context expects a negative adjective that expresses difficulty.
The term steadily refers to something firmly fixed, supported, or balanced. This is fitting for the second blank as it can be used to describe a manner of walking. In this case, a plod (heavy) can be done steadily, but not quickly.