If you were reporting on having attended an exhibition last summer, what sentence would you choose as your most natural style of usage?
"I heard the Pops at the Esplanade last summer."
"I went to Boston MFA for the photography exhibit last week."
The verb would depend on the occasion : music= I heard; paintings= I saw; baseball game or another athletic event = I went to.


2. If someone had kept you waiting for a meeting outside a shop, say, what sort of construction would you use if reproving them about their final arrival (please incorporate a variant of those last two words)

When a teen I learned that since I try very hard to be on time and others are sometimes delayed I always arrange to meet somewhere comfy, if wait I must!
It would be up to the late arrival to offer an explanation for being tardy.

I would probably say : "I ordered tea, sit down and catch your breath."
However, if I was really upset, and the meeting was important, and time for it was short, and I knew the person very well, or it was someone I was paying, or it was a family member I would smile (or frown if they were more than 15 minutes late) and say : "What kept you?" while sipping my tea.

"Final arrrival" does not feel comfortable to this American ear in the circumstances you set forth. More suited to a funeral!
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