Does change in shape of a body, while applying force to move it to a certain distance, cause any change in the work done on the body? While reading a physics book, the lesson "Work and Kinetic Energy" to be specific, I came across these sentence " Consider a body that undergoes displacement of magnitude s along a straight line. (For now, we'll assume that any body we discuss can be treated as a particle so that we can ignore any rotation or changes in the shape of the body.)..." 
I know that in case of a rolling body, there exist rotational kinetic energy along with translational (which can possibly contribute to the value of work done). So, the author wants to make the case simple by eliminating the rotation.But why does he want to eliminate the change in the shape of the body?
I wanted to know how does the change in shape affect the kinetic energy or work done on the body?
 A: The total work done, if the body is not a point is just the sum(or in your case integral) of $F.\vec{ds}$ of all the individual points of the body. The same is true for anything including rotation of a body also. The rotational kinetic energy terms just comes by simplifying the expression which includes different velocity of different points in a body.  
A: The work done on the body is always equal to $$
dW = \Sigma_i\; \vec{F_i}\cdot d\vec{r_i}$$
where $i$ counts every (infinitely) small piece of the body you are looking at. $\vec{F_i}$ is the force on the $i$-th piece, while $d\vec{r}_i$ is the displacement of the corresponding piece. In general, for an arbitrary body, this can be extremely difficult to evaluate. This is because $d\vec{r}_i$ can widely differ, depending on the $i$. This is why your book considered only "simple" motions, like translation and rotation.
In the case of translation $d\vec{r}_i = d\vec{r}$, i.e. it is independent of $i$. Then:
$$
dW = \vec{F} \cdot d\vec{r}
$$
where $\vec{F}$ is now the full force on the whole body and $d\vec{r}_i$ is the displacement of the whole piece.
Having in mind everything said so far, changing the shape of the body (while an external force is acting on it) does indeed cause the work to be done. In general this is hard to evaluate, so most physics textbooks usually deal with simplified versions where the shape does not change (for example in the case of "hard" balls).
