Learn Hardcore Spanish (Spain): Mi amiga echa de menos a su pareja, pues viaja mucho por trabajo. - My friend misses her partner, since she travels a lot for work.

Because of the Spanish personal a, used before a direct object that is a specific person or pet. With the idiom echar de menos a alguien, the person you miss is a direct object, so you must say a su pareja. With things or places you normally omit it: Echo de menos Madrid, Echo de menos el verano.

Can I use extrañar instead of echar de menos?

Yes. In Spain, echar de menos and echar en falta are the most common; extrañar is much more common in Latin America, but it’s understood everywhere. Examples: Mi amiga extraña a su pareja; Mi amiga echa en falta a su pareja.

How would I replace a su pareja with a pronoun?

If the partner is female: Mi amiga la echa de menos.
If the partner is male: Mi amiga lo echa de menos.
In much of Spain, leísmo is accepted for a masculine human direct object, so you may also hear: Mi amiga le echa de menos (only if the partner is male). Placement: the clitic goes before the conjugated verb, or can attach to an infinitive/gerund: Va a echarla de menos, Está echándola de menos.

Why is it echa and not echo/hecha?

echa is 3rd‑person singular of echar (she/he throws → here, part of the idiom).
echo (no initial h) is 1st‑person singular: Yo echo de menos....
hecha (with initial h) is the feminine participle of hacer (“made/done”) and does not belong here. Do not write hecha de menos.

Who is the subject of viaja here?

It’s ambiguous without an explicit subject. Many readers will infer it’s the partner (that travel is the reason she misses them), but it could also refer to the friend. To make it clear:

Partner travels: ..., pues su pareja viaja mucho por trabajo.
Friend travels: ..., pues ella viaja mucho por trabajo. You can also use él/ella or repeat the noun: ..., pues Ana viaja... / su pareja viaja....

Why use pues instead of porque?

Both are correct. pues here means “since/because” and often feels a bit more explanatory or stylistically neutral/formal in Spain. porque is the default “because.” Alternatives: ya que, puesto que, or como at the start: Como viaja mucho..., mi amiga....

Is the comma before pues necessary?

It’s common and recommended in this causal use to mark the explanatory clause: ..., pues viaja.... With porque, you typically do not use a comma: Mi amiga echa de menos a su pareja porque viaja.... The comma also helps avoid reading pues as the filler “well.”

Why not está viajando mucho instead of viaja mucho?

Spanish prefers the simple present for habits: viaja mucho = “travels a lot (habitually).” está viajando mucho highlights a temporary “right now” phase. For a general reason, the simple present is better.

Why por trabajo and not para trabajo? Could I say por su trabajo or por el trabajo?

Use por for motive/reason. viaja por trabajo = “travels for work/business.” para trabajo is not idiomatic here. Variants:

por su trabajo = because of her/his specific job.
por el trabajo = because of the work (generic or previously mentioned).

Does pareja tell you the partner’s gender or marital status?

No. pareja is gender‑neutral and does not imply marriage. It can mean boyfriend/girlfriend, partner, or spouse. Context or pronouns show gender if needed: su pareja; él/ella.

“Su” is ambiguous. How can I make it clear it’s “her partner”?

Rephrase to name the possessor: Mi amiga echa de menos a la pareja de mi amiga (better: repeat the name if known: Mi amiga Ana echa de menos a la pareja de Ana). More naturally, keep su pareja and clarify the traveler with a pronoun or noun: ..., pues él/ella (su pareja) viaja mucho....

Why mucho and not muy?

mucho modifies verbs: viaja mucho. muy modifies adjectives/adverbs: viaja muy rápido, está muy cansada. You can intensify with muchísimo: viaja muchísimo.

Can I front the cause with como/ya que?

Yes:

Como su pareja viaja mucho por trabajo, mi amiga la echa de menos.
Ya que su pareja viaja mucho por trabajo, mi amiga la echa de menos. When the causal clause comes first, put a comma after it.

Is echar en falta also correct?

Yes. It’s a near‑synonym common in Spain: Mi amiga echa en falta a su pareja.

Could I say Le hace falta su pareja?

Grammatically yes, but it leans toward “she needs/lacks her partner.” For the emotional sense of “miss,” echar de menos or echar en falta is more idiomatic.

Can I use clitic doubling with the direct object?

Yes, especially with animate objects when topicalized: A su pareja la echa de menos (mi amiga). This is natural in Spain.

Is pues ever just a filler like “well”?

Yes: Pues, no lo sé. In your sentence, because of the comma and what follows, pues is causal (“since/because”), not the filler.