بينما يحفر أبي الثقب، تكون النظارات الواقية على وجهي.

Here بينما means while / as. It introduces a clause describing something happening at the same time as the main clause.

So in:

بينما يحفر أبي الثقب

the whole part after بينما is a full clause: يحفر أبي الثقب = my father is digging/drilling the hole.

In other contexts, بينما can also mean whereas, but here it is clearly temporal: two actions/states happening simultaneously.

In Arabic, the present tense often covers both:

• simple present: he digs
• present progressive: he is digging

The surrounding context tells you which meaning is intended. With بينما and a simultaneous action, يحفر is naturally understood as is digging / is drilling.

Also, يحفر is 3rd person masculine singular: he digs / he is digging.

Because Arabic very often uses verb–subject–object order.

So:

• يحفر أبي الثقب = My father is drilling the hole
• literally: drills my father the hole

This is normal Arabic word order.

You could also say:

أبي يحفر الثقب

That is also correct, but it is more subject-first, a bit like putting focus on my father. The version in your sentence is a very standard verbal sentence pattern.

Because أبي is:

• أب = father
• ـي = my

So أبي literally means father of me, that is, my father.

A few useful points:

• once a noun takes a possessive suffix like ـي, it becomes definite by itself
• because of that, you do not add الـ
• so أبي is correct, not الأبي

In this sentence, أبي is the subject of يحفر.

Normally, Arabic nouns show case, and the subject is nominative. Here, أبي is indeed the subject, so it is nominative in function.

However, with a word like أبي (a noun with the possessive suffix ـي), the case is not clearly visible in the usual way. So for a learner, the most important point is:

• أبي = my father
• in this sentence it functions as the subject

You do not need to expect a clearly written nominative ending here.

الثقب means the hole, with الـ making it definite.

Arabic often uses the definite form when the thing is understood from the situation or is a specific hole being discussed. So the sentence is talking about the hole, not just any hole.

If the meaning were a hole, Arabic would usually use an indefinite form, such as ثقبًا in the appropriate structure.

Not only dig. The verb حفر can mean:

• to dig
• to bore
• to drill
• to make a hole

The exact English translation depends on context. With الثقب (the hole), it often suggests drilling / making a hole, not just digging in soil.

So if the context is tools, wood, walls, or construction, drill may be the best English choice.

Yes, it could.

In Arabic, the present-tense is / are is often omitted in simple nominal sentences. So:

النظارات الواقية على وجهي

can mean:

The protective glasses are on my face.

That is very normal Arabic.

Adding تكون makes the statement more explicit. Depending on context, it can sound like:

• are
• are to be
• should be
• remain

So the version with تكون is grammatical, but a learner should know that Arabic often leaves out the present-tense copula in this kind of sentence.

Because النظارات is a non-human plural noun.

In standard Arabic, non-human plurals are usually treated grammatically as feminine singular for agreement. That affects verbs, adjectives, and pronouns.

So even though النظارات refers to more than one item, Arabic commonly agrees with it as feminine singular:

• تكون = feminine singular
• not a regular plural verb

This is a very important rule in Arabic grammar.

For the same reason: النظارات is a non-human plural, so its adjective usually appears in the feminine singular in standard Arabic.

So:

• النظارات = plural noun
• الواقية = feminine singular adjective

That may look strange to an English speaker, but it is normal Arabic agreement.

If the noun were a human plural, the adjective would normally be plural too. But with non-human plurals, feminine singular agreement is the standard pattern.

It breaks down like this:

• على = on
• وجه = face
• ـي = my

So وجهي means my face, and على وجهي literally means on my face.

Like أبي, وجهي is a noun with a possessive suffix. That means:

• it is already definite
• you do not add الـ

So وجهي is correct for my face.

It can do both.

1. Temporal: while / as

   • two things happen at the same time

2. Contrastive: whereas

   • comparing two different situations

In your sentence, it is clearly temporal, because it links your father's action with the state of the safety glasses at the same time.