……. is a very useful tool in your ‘speak-like-a-native toolkit’. It has two main meanings / uses according to the Oxford English Learners Dictionary: http://www.oxfordlearnersdictionaries.com/ , my trusted friend
Firstly, it means “to be expected or required to do/be something according to a rule, a custom, an arrangement, etc. “
A rule = “You’re supposed to buy a ticket, but not many people do.“ By the way (BTW) “Schwarzfahren“ isn’t “black driving“, we would probably best translate it by ”to fare-dodge“.
A custom = “Aren’t we supposed to get paid our annual bonus in Novemember.“
An arrangement = “You were supposed to be here an hour ago!“
Here are two other common situations that we use this construction:
When you are annoyed by what somebody said “What is that supposed to mean?“
When you are unsure about what is expected of you in a situation,
“What time do we have to be home?“ or “What time are we supposed to be home”.
“Is it necessary to apply for a visa?”
or “Are we supposed to apply for a visa?“
Secondly, it is used to talk about what is generally believed or expected to be/do something “I haven’t seen it myself, but it’s supposed to be a great film“.
Thirdly, “not be supposed to do something“ means that you are not allowed to do something e.g. “You’re not supposed to walk on the grass.“
Pack your toolkit with this “be supposed to” and see you tomorrow.
my trusted friend (meinen vertrauten Freund), custom (Brauch), “What is that supposed to mean?“ (hier: “Was soll das heißen”)
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