Suggest improvements for the highlighted problem areas:
Panga and me took some tourists on a singing tour of the Congo. I steered the boat while Panga strummed on his guitar and watched for crocodiles. At Malebo Pool our tourists reacted with frightened grimaces to me singing.
They asked Panga and I to humor them with a non-musical tour. We obliged them until we came upon some rough rapids. Here, several of the tourists were surprised when they heard my singing a solo. But they were too worried by the approaching cataracts to complain.
- Pronoun Case: Verbal -
Sometimes it may look like a gerund, but is instead a verbal. Our previous examples, slightly modified, place the pronoun in front of a verbal, and so do not require the possessive case:
She heard him begging for attention.
I imagined us winning the race.
Panga noticed them rowing his boat.
Which brings us to another error in the opening paragraph:
Here, several of the tourists were surprised when they heard my singing a solo.
Here singing is not a gerund or a noun. It is a verbal, and the pronoun is now the object of the verb heard preceding it. Therefore, the objective case is required:
Here, several of the tourists were surprised when they heard me singing a solo.