In “People like [to go to the beach] and [swim in the sea].”, shouldn’t there be a “to” in front of “swim”?

You’re absolutely right to notice the lack of “to” before “swim.” However, in this specific sentence, it is grammatically correct without “to.”

Here’s why:

Parallel structure: The sentence uses parallel structure with the verbs “go” and “swim.” Both verbs are in the infinitive form (“to go” and “swim”), but the “to” is omitted before “swim” to maintain the parallelism and create a smoother flow.

Understood “to”: Even though “to” is not explicitly stated before “swim,” it’s understood to be there. The sentence could be written as “People like to go to the beach and to swim in the sea,” but omitting the second “to” is more concise and natural.

Common with infinitives: This is a common pattern with infinitives connected by “and” or “or.”

Examples:

“She wants to sing and dance.”
“He needs to study and work.”
“They decided to eat out or order in.”
Key takeaway:

While infinitives usually have “to” before them, it can be omitted when two or more infinitives are joined by “and” or “or” to create a parallel structure. This is grammatically correct and often preferred for conciseness and flow.