Questions & Answers about Мне трудно учить новые слова без словаря.
Why is there no explicit subject in the phrase мне трудно, and what kind of construction is this?
This is an impersonal construction. Russian often omits a grammatical subject when expressing sensations or states like difficulty, cold, or hunger. Instead of “It is hard for me,” you literally say “To me (мне) [it is] hard (трудно),” with no subject pronoun.
Why is мне in the dative case rather than the nominative?
In impersonal constructions expressing feelings or states, the person who experiences that state takes the dative case. Here мне (dative of я) marks the experiencer of the difficulty.
What part of speech is трудно, and how does it function in this sentence?
Трудно is a predicative adverb (or modal word) used as the main “verb” of an impersonal construction. It describes the difficulty of the action for the experiencer.
Why is учить in the infinitive form, and which aspect does it have?
Учить is an imperfective infinitive, showing an ongoing or repeated action: “to study/learn” new words in general. Infinitives in Russian often follow words like трудно, because they describe what is hard to do.
Could you use выучить instead of учить, and what difference would it make?