This is the 530th most frequent Chinese word.
几乎
Almost; nearly.
The word '几乎' is used here to indicate that the action of running happens on nearly every day, but with slight exceptions.
他几乎每天都去跑步。
He almost runs every day.
The word '几乎' serves to express that very few, if any, people are capable of answering the question.
这个问题几乎没人能回答。
Almost no one can answer this question.
The word '几乎' describes that the speaker is very close to finishing the task, but it is not yet fully completed.