Spanish adverbs
Adverbs are words that describe verbs or adjectives. They don't have gender or number. Here's an important one:
muy - very
Yo estoy muy cansado. (I am very tired.)
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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.