Im Supermarkt frage ich, ob die Linsen im Angebot sind oder ob ich lieber Bohnen kaufen soll.

German often puts a time/place/detail element first to set the scene. Here, Im Supermarkt means in the supermarket, so it tells you where the action happens before telling you what the speaker does.

Starting with Im Supermarkt is very natural in German. It gives the sentence this structure:

• Im Supermarkt = first position
• frage = verb in second position
• ich = subject after the verb

So German is not just copying English word order here.

In a normal main clause, German uses the V2 rule, which means the finite verb must be in the second position.

If the sentence began with Ich, then you would get:

• Ich frage ...

But because Im Supermarkt comes first, the verb still has to stay second:

• Im Supermarkt frage ich ...

So ich moves after the verb. This is one of the most important German word-order patterns to get used to.

Im is a contraction of:

• in dem → im

So Im Supermarkt literally comes from in dem Supermarkt.

German very often contracts certain preposition + article combinations, and this is one of the most common ones.

Also, dem is dative, because the sentence describes a location where something happens, not movement toward a place.

• im Supermarkt = in the supermarket
• compare movement: in den Supermarkt = into the supermarket

Ob means whether or sometimes if in the sense of whether.

In this sentence:

• ob die Linsen im Angebot sind = whether the lentils are on sale
• ob ich lieber Bohnen kaufen soll = whether I should buy beans instead

A very important point: German ob is used for indirect yes/no questions.

So after frage ich (I ask), the speaker is asking whether something is true.

It is repeated because there are two separate indirect question clauses joined by oder:

• ob die Linsen im Angebot sind
• oder ob ich lieber Bohnen kaufen soll

This is very natural German. Repeating ob makes both alternatives clear and balanced.

In English, we might say:

• I ask whether the lentils are on sale or whether I should buy beans instead.

So the repeated whether works the same way.

Because clauses introduced by ob are subordinate clauses, and in German subordinate clauses normally send the finite verb to the end.

So:

• ob die Linsen im Angebot sind
• ob ich lieber Bohnen kaufen soll

This is a core German pattern:

• main clause: verb second
• subordinate clause: verb last

That is why you get:

• frage ich in the main clause
• but sind and soll at the ends of the ob clauses

Im Angebot means on sale, on special, or being offered at a reduced price, depending on context.

So:

• Die Linsen sind im Angebot = The lentils are on sale

Literally, it comes from in the offer, but in normal English you would usually say on sale or special offer.

This is a very common supermarket/shopping expression in German.

This is a very common thing learners notice.

• die Linsen refers to the lentils as a specific item being discussed, probably the lentils in the store
• Bohnen without an article is more general: beans as something to buy

After verbs like kaufen, German often uses a bare plural when talking about something in a general, non-specific way.

So:

• die Linsen = the lentils
• Bohnen kaufen = buy beans

If you said die Bohnen kaufen, that would sound more like buy the beans, meaning some specific beans already identified.

Lieber here means rather, preferably, or instead.

In this sentence:

• ob ich lieber Bohnen kaufen soll

the idea is:

• whether I should rather buy beans
• or more natural English: whether I should buy beans instead

So lieber shows preference between options.

You will often see it in sentences like:

• Ich trinke lieber Tee. = I prefer drinking tea.
• Willst du lieber Kaffee? = Would you rather have coffee?

Soll is from sollen, which often means should, be supposed to, or ought to.

Here it expresses something like what would be advisable:

• ob ich lieber Bohnen kaufen soll = whether I should buy beans instead

It does not necessarily mean a strong obligation. In everyday speech, it can simply mean asking for guidance or advice.

So the speaker is wondering what makes more sense to buy.

Because soll agrees with the subject, not with the object.

The subject here is ich, so the verb must match ich:

• ich soll

Bohnen is the thing being bought, so it is the object, not the subject.

Structure:

• ich = subject
• Bohnen = object
• kaufen soll = verb phrase belonging to ich

Usually, when talking about lentils as food, German commonly uses the plural Linsen, much like beans in English.

So:

• die Linsen = the lentils

You may also encounter singular die Linse, but that often refers to:

• a lens
• a lentil as a single item, depending on context

In everyday food/shopping contexts, Linsen in the plural is very normal.

Yes, the main clause could be rearranged, as long as the finite verb stays in second position in the main clause.

For example:

• Ich frage im Supermarkt, ob die Linsen im Angebot sind oder ob ich lieber Bohnen kaufen soll.

This is also correct.

The difference is mainly in emphasis:

• Im Supermarkt frage ich ... puts the location first
• Ich frage im Supermarkt ... puts the speaker first

Both are grammatical and natural.