Question

1. I would rather die than surrender.
2. I would rather fail than cheat.
3. I would rather play games than study.
4. I would rather walk to work than go to work by car.
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Are they all grammatical? Do we have to use the base verb after 'than'? Can we use a 'to-infinitive' after 'than'? What is the part of speech of 'than' in each sentence? What could be the full form of 'the expression' after 'than'?

Answer 1

These are all fine, yes.

You can either use the base verb or the infinitive, although the infinitive form is a bit wordy. Most people don't use it in this expression.