Learn Hardcore French: Le pont est délicat, alors marche lentement.

Alors serves as a conjunction, meaning "so" or "therefore." It links the two clauses—first stating that the bridge is delicate, and then giving the consequent instruction to walk slowly. This shows a cause-and-effect relationship.

Why is marche used in its imperative form without a subject pronoun?

In French, when giving a command, the imperative mood is used. Marche is the singular, informal imperative form of the verb marcher. In the imperative, the subject pronoun (usually tu for the informal singular) is omitted, making the command direct and concise.

What does the adjective délicat imply about the bridge?

Although délicat literally translates as "delicate," in this context it suggests that the bridge is fragile or unstable. It implies that caution is needed when crossing, which is why the instruction to walk slowly is given.

Why is there a comma between "Le pont est délicat" and "alors marche lentement"?

The comma separates two closely related independent clauses. It helps clarify that the condition described in the first clause (the delicate nature of the bridge) is directly connected to the advice given in the second clause (to walk slowly).

Could a different imperative form of marcher have been used here, and why is marche chosen?

Yes, the formal or plural imperative marchez could have been used if the instruction were directed at more than one person or in a formal context. Marche is chosen here because it is the informal singular form, suggesting that the command is addressed to one person in a familiar tone.