The phrase "are merely expressions" is correct and usable in written English.
It can be used to indicate that something is simply a way of conveying an idea or feeling, without deeper significance.
Example: "The phrases we use in everyday conversation are merely expressions of our thoughts and emotions."
Alternatives: "are just phrases" or "are simply representations".
Skeptics argue that statements about right and wrong are merely expressions of preferences.
Political signs are merely expressions of free speech, said Henry Miga, the zoning enforcement official and building official in Granby.
In the next section we will return to the position that moral claims are merely expressions of attitude, a position consistent with the fact of moral disagreement.
If moral evaluations are merely expressions of feeling without propositional content, then of course they cannot be inferred from any propositional premises).
Those are merely expressions of Love from another to us, but it is not the core essence of Love.
Wales players have defended their actions in celebrating Iceland's elimination of England from Euro 2016 after footage of them enjoying the 2-1 victory emerged on social media, claiming the wild scenes were merely expressions of pride at becoming the only side from Britain and Ireland to make the quarter-finals.
It is obvious, and often noted, that fashion doesn't have to be misogynistic and exclusionary; fashion is merely expression, and expression is morally neutral.
No one wants the lights to go out, and all our valiant attempts to illuminate the night are merely fearful expressions of the permanent darkness that awaits.
The Tea Party and libertarian objections to taxes, the social safety net, and corporate and environmental regulations are merely absolutist expressions of this same idea: less government always equals more freedom.
And yes, we reached a pinnacle of self-discovery by realizing that we are merely one expression of an awesomely complex and ancient system of molecular machinery, evolving and selecting itself across the ages.
The revenue and user growth, however, are merely an expression of results.
