Is it the case that if $\sum_{n=1}^{\infty}{a_n}$ diverges then $\sum_{n=1}^{\infty}{|a_n|}$ also diverges?
It seems obvious that if $\sum_{n=1}^{\infty}{a_n}$ is unbounded (i.e., $\lim_{n\rightarrow\infty}{S_n}\rightarrow \infty \text{ or }-\infty$) then $\sum_{n=1}^{\infty}{|a_n|}$ is also unbounded and the claim follows for this case.
But for other cases, I find it a bit tricky.
Note: $S_n$ denotes $n$th partial sum.