For concreteness consider just two specific events (Event A and Event B) as observed by a physical observer (say, a scientist on earth): Event A is the observer sees a photon at time $t_A$ atpasses the location $x_A$ at time $t_A$ (theI'll take the x axis is inas the direction of travel of the photon); Event B is the observer sees a photon is as location $x_B$ at time $t_B$ at the location $x_B$.
Suppose now that different physical observer is observing these same eventevents, but now from a frame that is moving with velocity $v$ in the x-axis direction. This different observer's measurements of the time and space intervals for Event A and Event B are related to the first observers measurements by a Lorenz transformation as:
$$
\Delta \tilde t = \gamma \Delta t(1-\frac{v}{c}) = \Delta t \sqrt{\frac{1-\frac{v}{c}}{1+\frac{v}{c}}}
$$
and
$$
\Delta \tilde x = c\Delta t\sqrt{\frac{1-\frac{v}{c}}{1+\frac{v}{c}}}\;.
$$
Now, you might look at my equation for $\Delta \tilde x$ and for $\Delta \tilde t$ and say "Hmm, if I set $v$ equal to $c$ in those equations then there is no distance and no time between the two events." But, of course, the Lorenz transformation matrices are infinite at $v=c$ so this approach is frowned upon.
Better yet you might say "Hmm, as $v$ approaches $c$ from below both $\Delta \tilde x$ and $\Delta \tilde t$ approach zero. But, although both $\Delta \tilde x$ and $\Delta \tilde t$ approach zero their ratio is always fixed (and equal to $c$ since it is a photon being observed).
One final point you may want to consider is that it is possible (and easy) to ask unanswerable nonsense questions. We can not stop you from stringing words together into sentences that look syntactically like well formed questions, but are semantic nonsense. For example: "What is the square root of a watermelon?" This is a syntactically proper sentence with a question mark at the end... but it is actually non-sensicalnonsense. These kind of questions dotend to not lead to anything very useful.
