Animals in the park

S→subject
V→verb
O→object
n→noun

When Grandpa(s) come(v)to visit(o)(noun), we (s)like(v)to go(o)for walk.
{Grandpa} is the third person singular, so add an -s at the end of {come}.
And we say {go for a walk}.
When Grandpa(s) comes(v)to visit(o), we (s)like(v)to go(o)for a walk.

First, we(s)go(v)to the store(o).
Ok!

Grandpa (s)buys(v)some seeds and nuts(o).
Ok!

Then we(s)go(v)to the park(o).
Ok!

Grandpa(s)shows(v)me(o/noun) how to feed the birds and squirrels.
Ok!

We(subject) give(verb) them seeds and nuts to eat. (noun) (to) (verb)

这句不太明白→Soon all the small animals come to me.
Soon(adv) all the small animals(s) come(v) to me.(o)

I (s)enjoy feeding them.→(noun)
Verb?
Doing is used as an object here.
I (s)enjoy(v) feeding them(o).

I(s)think(v)they(o/n)like seeds and nuts, and they (s)like(v)us(o/n)too.
There is a clause here.
I(s)think(v)(they like seeds and nuts)(clause of objective), and they (s)like(v)us(o/n)too.