Hoe versigtig sy die binneband ook al lap, toets ons dit.

It means however ... or no matter how ....

So:

• Hoe versigtig sy die binneband ook al lap
  = No matter how carefully she patches the inner tube

This is a very common Afrikaans pattern for expressing concession: something is true despite whatever happens in the first clause.

No. Even though hoe often means how in questions, here it is not a real question word.

In this sentence, hoe ... ook al is a fixed pattern meaning:

• however
• no matter how

So the sentence is making a statement, not asking anything.

Afrikaans usually does not have a separate -ly adverb form like English does.

So:

• versigtig = careful
• versigtig can also mean carefully

The same word can function as an adjective or an adverb depending on context.

Here it is adverbial, because it describes how she patches the tube:

• Hoe versigtig sy ... lap
  = How carefully she patches ...

Because the first part is a subordinate clause introduced by hoe.

In Afrikaans, subordinate clauses typically send the verb to the end. That is why you get:

• sy die binneband ook al lap

rather than:

• sy lap die binneband ook al

So the structure is normal Afrikaans subordinate-clause word order.

In this sentence, ook al is part of the concessive pattern hoe ... ook al.

It adds the sense of:

• no matter how
• however
• even if it is very much the case that

So ook al is not just random extra emphasis here; it helps build the whole meaning of concession.

You should learn hoe ... ook al as a chunk.

Here lap is a verb meaning:

• patch
• mend
• repair with a patch

Because the object is die binneband (the inner tube), lap specifically means patching a punctured tube.

So:

• sy die binneband lap
  = she patches the inner tube

Binneband means inner tube, such as the tube inside a bicycle tire.

It is a compound word:

• binne = inside / inner
• band = tire / tyre / band, depending on context

So binneband literally means something like inside tire, but the natural English meaning is inner tube.

Because the sentence begins with the whole first clause:

• Hoe versigtig sy die binneband ook al lap

In Afrikaans main clauses, the finite verb usually comes in second position. Since the first position is already occupied by that entire clause, the verb comes next:

• toets ons dit

If the sentence started directly with the subject, then you would say:

• Ons toets dit

So this is normal verb-second word order after a fronted clause.

Dit refers to die binneband.

So after she patches the inner tube, we test it.

Afrikaans commonly uses dit for it when referring to things. Unlike languages with grammatical gender, Afrikaans does not change the pronoun based on masculine/feminine noun gender.

Yes. In this sentence, sy means she.

You can tell from its role in the clause:

• sy die binneband ... lap
  = she patches the inner tube

So sy is the subject of lap.

This is worth noticing because sy can look confusing to English speakers, especially since Afrikaans pronouns do not always map neatly onto English forms.

The comma separates the fronted subordinate clause from the main clause.

So the structure is:

• Hoe versigtig sy die binneband ook al lap,
  subordinate clause

• toets ons dit.
  main clause

This is similar to English punctuation in sentences like:

• No matter how carefully she patches the inner tube, we test it.

The comma helps show where the first clause ends and the main statement begins.