Think of the tools in a tool-box: there is a hammer, pliers, a saw, a screwdriver, a rule, a glue-pot, nails and screws.--The function of words are as diverse as the functions of these objects.
There are remarks that sow and remarks that reap.
You might say that certain words are only pegs to hang intonations on.
One is unable to notice something because it is always before one's eyes.
Belief in the causal nexus is superstition.
What can be shown, cannot be said.