عندما تكون بطارية هاتفي ضعيفة، أشحنه في البيت قبل أن أخرج.

عندما means when and introduces a time clause.

So:

• عندما تكون بطارية هاتفي ضعيفة = when my phone battery is low

It is very common in MSA to use عندما before a clause with a present-tense verb to talk about something that happens regularly or whenever a situation occurs.

In this sentence, the speaker is not talking about one single event only. It sounds more like a habit:

• Whenever my phone battery is low, I charge it at home before going out.

Because its subject is بطارية (battery), and بطارية is a feminine noun.

In Arabic, verbs often agree with their subjects in gender. Since بطارية is feminine singular, the verb is feminine singular too:

• تكون = it is / it becomes (feminine)

If the subject were masculine, you would use يكون instead.

For example:

• عندما يكون هاتفي جديدًا... = when my phone is new...
• عندما تكون بطارية هاتفي ضعيفة... = when my phone battery is low...

In standard Arabic, after عندما, you normally use a verbal clause, so تكون makes the structure natural and grammatical in MSA.

• عندما تكون بطارية هاتفي ضعيفة = natural MSA
• عندما بطارية هاتفي ضعيفة = not standard in this context

Literally, تكون here is like is or is being. But in smooth English, you would usually just translate the whole part as:

• when my phone battery is low

So even though Arabic explicitly uses a verb, English may not need to show that in the same way.

Because it describes بطارية, which is feminine.

Arabic adjectives agree with the nouns they describe in:

• gender
• number
• definiteness

Here:

• بطارية = feminine singular
• so the adjective must also be feminine singular: ضعيفة

Compare:

• هاتف ضعيف = a weak phone (masculine)
• بطارية ضعيفة = a weak battery (feminine)

In context, ضعيفة means weak or more naturally low.

This is a possessive construction called iḍāfa.

• بطارية = battery
• هاتفي = my phone

Together:

• بطارية هاتفي = the battery of my phone = my phone battery

This is a very common Arabic way to express possession.

A few things to notice:

1. The first noun usually does not take ال in an iḍāfa.

   • So we say بطارية هاتفي, not البطارية هاتفي

2. The whole phrase becomes definite because هاتفي is definite.

   • So بطارية هاتفي means the battery of my phone / my phone battery, not just a battery of my phone

هاتف means telephone / phone.

When you add ـي, it becomes my phone:

• هاتف = phone
• هاتفي = my phone

That ـي is the first-person singular possessive suffix.

Other examples:

• كتابي = my book
• بيتي = my house
• سيارتي = my car

So:

• بطارية هاتفي = the battery of my phone

Because the pronoun ـه refers to هاتفي (my phone), which is masculine.

• أشحنه = I charge it (masculine object)

Even though the earlier noun بطارية is feminine, the meaning here is:

• When my phone battery is low, I charge the phone

So the speaker is charging the phone, not specifically the battery as a grammatical object.

If you said أشحنها, the pronoun would refer to بطارية:

• أشحنها = I charge it (feminine), meaning I charge the battery

Both are grammatically possible, but they refer to different things.

أشحن comes from the verb شحن and means I charge.

So:

• أشحنه = I charge it

This is the usual verb used for charging phones, batteries, devices, and similar things.

Examples:

• أشحن هاتفي = I charge my phone
• أشحن البطارية = I charge the battery
• أشحنه في البيت = I charge it at home

في البيت means in the house or more naturally at home.

• في = in / at
• البيت = the house / home

So:

• أشحنه في البيت = I charge it at home

Arabic often uses البيت where English might prefer home rather than the house.

This phrase expresses location, not movement. That is why في is used, not إلى.

• في البيت = at home
• إلى البيت = to the house / homeward

قبل أن means before followed by a verb:

• قبل = before
• أن = a particle that introduces a following verb
• أخرج = I go out / I leave

So:

• قبل أن أخرج = before I go out

This is a very common pattern in Arabic:

• قبل أن أنام = before I sleep
• قبل أن أذهب = before I go
• قبل أن آكل = before I eat

Yes. In grammar terms, أن normally puts the following present-tense verb into the subjunctive.

In fully vocalized Arabic, there would be a case-ending difference. For أخرج:

• indicative: أخرجُ
• subjunctive after أن: أخرجَ

But in normal unvocalized writing, both are written the same way:

• أخرج

So learners often do not see the difference in ordinary text, but grammatically it is there.

Because in Arabic, the present tense often covers:

• present actions
• habitual actions
• repeated actions
• general truths

So this sentence means something like:

• When my phone battery is low, I charge it at home before I go out
• or Whenever my phone battery is low, I charge it at home before going out

You do not need a special verb form for habitual actions here. The context and عندما make that meaning clear.

Yes. The adjective ضعيفة literally means weak.

But with batteries, Arabic commonly uses weak in places where English often says:

• low
• weak
• running low

So:

• بطارية هاتفي ضعيفة literally: my phone battery is weak
• natural English: my phone battery is low

This is a good example of where a literal translation is understandable, but a more natural English translation sounds better.

It has three parts:

1. عندما تكون بطارية هاتفي ضعيفة

   • When my phone battery is low

2. أشحنه في البيت

   • I charge it at home

3. قبل أن أخرج

   • before I go out

So the overall pattern is:

• When X happens, I do Y before Z.

This kind of structure is very common in Arabic and useful for describing routines.

Yes. Arabic word order is fairly flexible, especially with adverbial phrases and subordinate clauses.

This version is very natural:

• عندما تكون بطارية هاتفي ضعيفة، أشحنه في البيت قبل أن أخرج.

But you could rearrange parts for emphasis, such as putting the main action first in some contexts. Still, the given order is clear and natural because it starts with the condition or situation:

• When my phone battery is low...

Then it tells you what the speaker does.

For learners, this is a very good model to follow.

Yes, mainly the endings.

A fully vocalized version could look like this:

• عِندَما تَكونُ بَطّارِيَّةُ هاتِفي ضَعيفَةً، أَشحَنُهُ في البَيتِ قَبلَ أَن أَخرُجَ.

A few advanced notes:

• تكونُ has a nominative ending
• بطاريةُ is the subject of تكون
• ضعيفةً is the predicate of تكون, so it is accusative
• أخرجَ is subjunctive after أن

In normal everyday Arabic writing, these short vowels are usually omitted, so learners usually see the simpler unvocalized form.