Guten Tag! 4.2 At the snack bar-2

der Imbiss---This is one of several words for a "snack bar". You might also see the words "der Schnellimbiss", "die Imbissbude" or "die Würstchenbude" ("sausage stand"). 

was wünschen Sie?---"What would you like?" Having started with "Bitte schön", the conventional request for information, Herr Aksoy chooses to ask more specifically.

ich möchte gerne...---"I would like...". "Ich möchte..." on its own could be also be used here without "gerne". Note that anything that you ask for will be in the accusative case! 

eine Bratwurst---"A (fried) sausage". Usually served with a roll. The German reputation for eating sausages is certainly borne out by the choice offered at their snack bars!

eine große...---a big (sausage)...

...oder eine kleine?---"...or a small (sausage)?" If the noun has already been mentioned immediately beforehand, it does not need to be repeated when you are describing it by means of an adjective.

bitte---please

der Ketschup---Unsurprisingly, this means "ketchup". Until the recent German spelling reform, it was spelled the same way as the English word.

Pommes---"Chips". From the French "Pommes frites". While "Pommes frites" is the version listed in German dictionaries, you are just as likely to hear "Pommes".

möchten Sie auch...?---"Would you like...?" See the conversation in the first section.

das Brötchen---"A bread roll". All nouns ending in "-chen" are neuter - including "das Mädchen". The suffix "-chen" means "little" or "small". 

gerne---Another word that is difficult to translate. "Gerne" on its own means "happily" or "willingly". The combination "Ja, gerne" translates as a more enthusiastic version of "Yes please!"

ein Euro achtzig---"One euro eighty (cents)".

eine Currywurst---"A curried sausage". Very few German words begin with "c", and many of those that do are - as here - imported from other languages.

ein Euro siebzig---"One euro seventy (cents)".

danke sehr---"many thanks" (literally: "thanks very")

zurück---Literally "back", but here we would translate it as "in return".

Guten Appetit!---"Enjoy your food!" or "bon appetit".