- hardly ever
- every week/month/year
- from time to time
Here are a few examples of how to use them in sentences:
- I never get up early on Sundays.
- My parents always travel in December.
The adverb of frequency comes after the verb to be: "I'm never late."
The adverb of frequency comes before a main verb: "He sometimes goes clubbing on Saturdays."
IMPORTANT: Use the affirmative with never and hardly ever, not the negative! - "He hardly ever stays in bed late."