Spanish negation
To make a sentence negative, we just place the word no right before the verb:
Yo soy alto. (I am tall.)
Yo no soy alto. (I am not tall.)
Ellos están en España. (They are in Spain.)
Ellos no están en España. (They are not in Spain.)
Progress, Vol. 1
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Desirable difficulties
If studying feels effortless, you're probably not learning much. A bit of struggle during practice is a good sign. Difficulty isn't the enemy of learning; it's the mechanism.