Frequency expressions

Contrary to frequency adverbs , frequency expressions usually go at the end of a sentence which verb is most of the time in simple present tense since we talk about habits . 

Ex : How often do you have English lessons? 

I have English lessons twice a week. 

To say how often something happens,

1) You can use a number, many or several followed by times + a day /week / month / year :

• Once a day /week / month / year
• Twice a day /week / month / year
• Three times a day /week / month / year
• Four times a day /week / month / year
• Several times a day /week / month / year
• Many times a day /week / month / year

2) We can also use 'every' + period of time:

• every morning
• every day
• every Tuesday
• every week
• every month...

3) We can also use a day of the week + -s introduced by ON

• We have English lessons on Mondays, Tuesdays and Thursdays