What rules make these comparative clauses grammatical? [closed]
- We invited more people than came.
- Fred reads more books than Susan reads.
These than-clauses which appear in a grammar book seems weird to me. Are they grammatically acceptable? What about the substitutions as below?
a. We invited more people than they came.
b. Fred reads more books than Susan does.
Solution 1:
[1] We invited more people than came.
[2] Fred reads more books than Susan reads.
Yes: [1] and [2] are both correct. "Than" is a preposition, and "came" and "reads" are comparative clauses functioning as complement of "than".
Comparative clauses are stucturally reduced in some ways relative to the structure of main clauses. In full, the clause in 1. would be *"We invited more people than people came". But no one would say that, in fact it's ungrammatical; instead the comparative clause is reduced to a single element, the verb "came".
Similarly, in [2] the comparative clause is reduced to just the verb "reads". In full it would be "Fred reads more books than Susan reads books", again ungrammatical.
a. We invited more people than they came.
b. Fred reads more books than Susan does.
a. is a doubly ungrammatical attempt to fill out the reduction in [1]. See my comments above.
b. is fine and a grammatically correct alternant to [2]. "Does" is also a reduced comparative clause understood as "Fred reads more books than Susan reads books".