"We eten een boterham" is used as the dutch equivalent of the present simple: 'we eat a sandwich (every day)'= 'we eten (elke dag) een boterham', but can also be used as present continuous: 'we are (now) eating a sandwich'='we eten (nu) een boterham'
You need context to know what the English translation is so Duolingo marks both answers as correct.
Another way of using the present continuous in Dutch is 'we zijn een boterham aan het eten', which also means 'we are eating a sandwich' This is always translated as a present continuous.
Hope this helps!
I would say not really.
You could but people won't because we don't eat sandwiches but boterhammen.
So you could only say that if you were in a diner that has actual sandwiches on the menu while you were talking to someone on the phone.
So not something you would hear daily (unless your are a waitress in a place that serves food they call sandwiches on the menu)
'We ate' is past tense, while 'we eten' is present tense, so 'we eten' can never mean 'we ate'. The two possible translations of 'we eten' are only 'we eat' and 'we are eating' (so only present tenses). It depends on the context which one is intended. If the sentence is 'We eten een boterham', the translation is probably 'We are eating a sandwich'
Dutch has two sets of most subject and object pronouns, referred to as emphatic and unemphatic forms. For the first-person plural subject pronoun, 'wij' is emphatic; 'we' is unemphatic.
In English, we often use the reflexive form for emphasis, in complex ways—if, for example, you wanted to say that you and your partner are making a donation to someone, you would say "We give it to them". If you want to emphasize that you are using your own money, rather than making a donation on behalf of your company or family, you could say "We give it to them ourselves." If you wanted to further emphasize that the two of you are handing it over to them personally, you could say "We ourselves give it to them."
In Dutch, for certain pronouns, you can also use a different form for emphasis. As Wikipedia puts it, "The stressed form retains the original full vowel, and is used when particular emphasis or contrast is needed", while "the unstressed form normally replaces the vowel with a schwa /ə/ and is used" when such emphasis is not needed or wanted. You can make the same distinctions with the second-person singular (jij/je), second-person plural (jullie/je), 3rd-person singular, feminine (zij/ze). and 3rd-person plural (also zij/ze), and similarly for the object pronouns.