Q: Can you say, “His arriving was unexpected”?
A: Yes, you can, though it would be more common (and in most cases more idiomatic) to say, “His arrival was unexpected.”
Here’s the Google scorecard: “his arrival was,” nearly 2.8 million hits, vs. “his arriving was,” only 49.
There may be a slight difference in meaning here between the noun “arrival” and the gerund “arriving.” (A gerund is a word that’s made of a verb plus “-ing” and that acts as a noun.)
“His arriving was unexpected” suggests to us that he wasn’t expected at all. “His arrival was unexpected” could also mean that he arrived early, late, or by some unexpected means.
When the verb “arrive” entered English in the 13th century (borrowed from the Old French ariver), it referred to a ship, its crew, or its passengers reaching shore.
But by the late 14th century, according to the Oxford English Dictionary, “arrive” was being used in a more general way for ending any kind of trip or simply reaching a destination.
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