A conjunction used to change the topic or introduce a new remark: 'by the way' or 'incidentally.'
時に、君に聞きたいことがあるんだが。
By the way, there's something I'd like to ask you.
時に、彼の連絡先は知っているかい？
By the way, do you know his contact info?
An adverb meaning sometimes or occasionally; similar to 'sometimes' and slightly more literary/formal.
時に人は、過去を振り返りたくなるものだ。
Sometimes people feel like looking back on the past.
彼は時に大胆な決断をする。
He sometimes makes bold decisions.
時に雨が降るので傘を持って行ったほうがいい。
It rains occasionally, so you'd better take an umbrella.
An adverb meaning precisely or exactly at that time; 'just then' or 'at that very moment.'
時に彼は部屋を出ていった。
He left the room at that very moment.
時に雨がやみ、太陽が顔を出した。
Just then the rain stopped and the sun appeared.