"glad"
felt
appreciate
appreciate
grateful
A four letter word starting with the letter a is able.
Fell, tell the, feel, hi, felt, ill
feet, feat, fear, felt, fest, feed, feel, fete, fern, fees, fens
It depends on what you mean by 'four letter word'. Thea has four letters, so yes it is. It is not a swear word, so it's not that kind of 'four letter word'.
The comparative form of "grateful" is "more grateful".
A four letter word for 'in addition to' is also.
Lard is a four letter word for grease.
A four letter word for Seizures is moon