Question

I congratulated him _____ his success.
1] ON
2] UPON
3] AT

Answer 1

The right answer is 1) ON

Answer 2

I congratulated him on his success.

• We need to understand that all the verbs have some definite preposition attached with them.
• Some other examples of the same kind of sentences are as follows: They congratulated me on my marriage.
• Nowadays, it has been observed quite often that the preposition "for" is also used in such cases.