El crimen sucedió ayer.

Because crimen is a masculine noun in Spanish, so it takes el.

• el crimen = the crime
• un crimen = a crime

This is something you just have to learn with the noun. The ending -en does not automatically tell you the gender, so it is best to memorise crimen together with el.

Also note that crimen stays the same in the singular, but the plural is los crímenes.

Sucedió is the preterite tense, third person singular, from the verb suceder.

So it means:

• it happened
• occurred

In this sentence, the subject is el crimen, so literally:

• El crimen sucedió ayer = The crime happened yesterday

The preterite is used here because it describes a completed event in the past.

The accent mark shows the correct stress: su-ce-DIÓ.

Without the accent, sucedio would not follow standard Spanish spelling rules for where the stress should go. The written accent tells you that the final syllable is stressed.

It also helps identify the form as the third person singular preterite of many -er and -ir verbs:

• comió
• vivió
• sucedió

Because sucedió refers to a single completed event: it happened, and that is it.

• sucedió = happened / occurred as a finished event
• sucedía = was happening / used to happen / happened repeatedly, depending on context

Since ayer gives a clear finished time in the past, the preterite is the natural choice:

• El crimen sucedió ayer = the crime happened yesterday

If you said El crimen sucedía ayer, it would sound wrong or at least very unnatural in normal usage.

Yes, but there are differences in style and usage.

• El crimen ocurrió ayer → very natural, often the most idiomatic choice
• El crimen sucedió ayer → correct, a bit more formal or literary
• El crimen pasó ayer → possible in some contexts, but less natural here than ocurrió

For events like crimes, accidents, or incidents, ocurrir is extremely common in Spanish.

So all of these may be understood, but ocurrió often sounds the most typical.

Yes, ayer can move.

All of these are possible:

• El crimen sucedió ayer.
• Ayer sucedió el crimen.
• Ayer el crimen sucedió. → grammatically possible, but less natural
• El crimen ayer sucedió. → possible, but marked or literary

The most neutral and natural version is the original:

• El crimen sucedió ayer.

Putting ayer first can add emphasis to the time:

• Ayer sucedió el crimen. = It was yesterday that the crime happened.

In Spain Spanish, both the preterite and the present perfect are used, but they are not used in exactly the same way.

With a finished past time such as ayer, Spanish normally prefers the preterite:

• Ayer sucedió. = correct and natural

Using ha sucedido with ayer is generally not standard in most careful Spain Spanish:

• Ayer ha sucedido → usually considered wrong or non-standard

In Spain, the present perfect is more natural with time periods connected to the present, such as:

• hoy
• esta semana
• este mes

Example:

• Hoy ha sucedido algo extraño.

But with ayer, use sucedió.

Often yes, but be careful.

Crimen usually means a serious crime. In many contexts it can sound stronger than the general English word crime. Spanish also has delito, which is a broader legal term for offence or crime.

Very roughly:

• crimen = often a serious crime
• delito = legal offence/crime in a broader sense

So El crimen sucedió ayer is understandable, but depending on context, a Spanish speaker might also say things like:

• El delito ocurrió ayer
• El asesinato ocurrió ayer if it was specifically a murder

A simple pronunciation guide is:

el kree-MEN soo-seh-DYOH ah-YEHR

A few key points:

• crimen stresses the second syllable: cri-MEN
• sucedió stresses the last syllable: su-ce-DIÓ
• ayer sounds roughly like a-YEHR

The c in crimen is a hard k sound. In sucedió, the c before e is pronounced differently in Spain Spanish and much of Latin America:

• In much of Spain: like th in think
• In most of Latin America: like s

So in Spain Spanish, sucedió sounds approximately like:

• soo-theh-DYOH

Yes, it is correct and understandable, but it sounds a little formal or like news/reporting language.

In everyday speech, many speakers might prefer:

• El crimen ocurrió ayer.

That said, El crimen sucedió ayer is still perfectly good Spanish. It just has a slightly more formal or narrative tone.