מזיק או מכרסם יכולים להיכנס למתקן האחסון.

Because the sentence is talking about two categories in a general way: a pest or a rodent. In practical Hebrew, especially in warnings or technical language, speakers often use a plural form when the overall idea is broad, like pests or rodents can get in.

So יכולים is masculine plural because:

• both nouns are masculine
• the sentence is generic, not about one specific animal

You may also come across singular יכול in similar sentences, but יכולים here sounds natural and general.

Yes — מזיק can be either:

• an adjective: harmful / damaging
• a noun: pest

In this sentence it is clearly a noun, because it is paired with מכרסם, another noun. So here מזיק means a pest, literally something that causes damage.

מכרסם is the standard Hebrew word for rodent. It comes from a verb meaning to gnaw, so the word is basically a gnawing animal.

That means it is broader than words like:

• עכבר = mouse
• חולדה = rat

So מכרסם is a category word, which fits well in a formal or technical sentence like this one.

All of those are possible depending on context.

In grammar terms, יכולים is the masculine plural form of יכול, which expresses ability or possibility. So יכולים להיכנס can mean:

• can enter
• are able to enter
• sometimes may enter in the sense of practical possibility

In a warning-style sentence like this, English often uses can.

These are two different ל- prefixes.

• להיכנס: the ל- is part of the infinitive, like English to enter
• למתקן: the ל- is the preposition to / into

So:

• להיכנס = to enter
• להיכנס למתקן = to enter the facility

English uses to only once, but Hebrew has one ל- for the infinitive and another ל- as a normal preposition.

Because this is a construct chain in Hebrew, called סמיכות.

The phrase is built like this:

• מתקן = facility / unit / installation
• אחסון = storage

Together:

• מתקן אחסון = a storage facility / storage unit

When a construct chain is definite, the ה- usually goes on the second word, not the first:

• מתקן אחסון = a storage facility
• מתקן האחסון = the storage facility

So the whole phrase becomes definite because האחסון is definite.

Because the sentence is speaking generically, not about a specific known pest or rodent.

So:

• מזיק או מכרסם = a pest or rodent / any pest or rodent
• המזיק או המכרסם would sound like the pest or the rodent, meaning a specific one already identified

Hebrew often uses bare singular nouns like this for general statements.

מתקן is a broad word. Depending on context, it can mean:

• facility
• installation
• unit
• device

In מתקן האחסון, the context makes it something like storage facility or storage unit, not a small gadget. Hebrew often uses one noun like מתקן where English chooses different words depending on the situation.

Yes. להיכנס is a very common everyday verb meaning to enter / go in / get into.

It is used with ל- before the place entered:

• להיכנס לבית = to enter the house
• להיכנס לחדר = to enter the room
• להיכנס למתקן האחסון = to enter the storage facility

So this sentence uses a very standard Hebrew structure.