1. He called on his uncle.

Question

2. He called at his uncle's (house).

3. He visited his uncle.
4. He visited his uncle's (house).

5. He dropped by the bakery/his grandma.
6. He came by the bakery/his grandma.

7. He paid a visit to his uncle.
8. He paid a visit to the bakery.
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Are they all grammatical? Are there any errors in usage? Do you have some more verbs which have similar meanings?

Answer 1

All are grammatically correct, but 4 and part of 5 and 6 don't make good sense.

4. I understand visiting his uncle, but why would he visit the house?

5. I understand dropping by the bakery, but not dropping by his grandma.

6. I understand coming by the bakery, but not coming by his grandma.

How can you fix those three things?

Answer 2

4. He visited his uncle.
5. He dropped by the bakery.
6. He came by the bakery.

Answer 3

Yes.

3 and 4 are the same.

5 and 6 are now fine.