Learn Spanish (Latin America): El guía pide que nos sujetemos por la velocidad altísima. - The guide asks that we hold on because of the extremely high speed.

To form the absolute superlative (meaning extremely or super), you drop the final vowel of the adjective and add -ísimo or -ísima. Here, alta (high) becomes altísima to match the feminine noun velocidad. Also, notice that all -ísimo endings always have a written accent on the first i!

Why is sujetemos in the subjunctive mood here?

The verb pedir (to ask or request) expresses a desire or command. When a person asks someone else to do something, it triggers the subjunctive mood for the second action. Here, pide que forces the verb sujetarse into its subjunctive form, nos sujetemos.

What is the purpose of the nos in nos sujetemos?

The verb used here is the reflexive sujetarse, which means to hold on or to secure oneself. The nos indicates that we are the ones holding ourselves secure. Without the reflexive pronoun, sujetar just means to hold or to fasten an external object.

Why do we use por instead of para in this sentence?