One trick to use when checking your grammar is to remove part of your sentence and see if it still makes sense.
I find this useful when considering if “I” should be used instead of “me”.
Think about the sentence I have just written and substitute “Me” for the initial “I” – “Me find this useful…” just does not make any real sense in that context and “I” is correctly used.
Now think about this sentence:
“They gave my father and I drinks at the pub.”
That sounds natural and correct to me but it is not correct – remove “my father” and you would have “They gave I drinks at the pub.” which sounds wrong and indeed it is – using “me” is better, so:
“My father and me were bought drinks at the pub.”
Now look at this example:
“My son and I went to the park.”
Removing “My son” leaves us with “I went to the park.” and that is correct – in this instance “I” is correctly used rather than me.
I see “myself” used to get around this grammatical conundrum but that just seems clumsy.