Think my answers are right but don't understand the following 3 clues

[Jaycee47]

1. Knock back excellent beer in ceremonial robes = Regalia (can see ai = excellent + ale = beer) where does r & g fit in?
2. Author's aim in dictionary is unlimited = Open ended (Pen = author). Don't understand rest of clue.
3. E.g. present Tees twists around close to Stockton = Tense (As present tense) Can see tees but where does the n come from and what's Stockton got to do with it?

[Prudie]

1 is A1 lager backwards

[vegasmad]

1. ai lager reversed

[bulliver]

1 'A1' (excellent) + 'lager' (beer) reversed = regalia

[vegasmad]

3. anagram of tees + (stockto)n

[Prudie]

2 pen + end (aim) in OED (Oxford English dictionary)

[bibblebub]

anagram of 'tees' outside the last letter, i.e. close, to stocktoN = N

[bulliver]

2 'pen end' in 'OED' (Oxford English Dictionary)

[vegasmad]

2. pen (author) end (aim) in oed (oxford english dictionary)

[Jaycee47]

Many thanks everyone. You are so clever!