This post contains tons of examples of how to use since, before, and ago. By the time you finish reading this, you’ll be a pro at using them!
These are just three of the 10 or so commonly-used prepositions for time. Future posts will cover additional prepositions of time.
I would suggest that you try memorizing these in context or as “chunks.” Don’t try to just memorize the rules of when to use them; memorize entire phrases like “since I started learning English” or “I met my wife 6 years ago.” Doing this helps you remember these words more automatically.
Use “since” to talk about a period of time from “then to now.” It is used to talk about things that are still happening, ongoing, or could happen again. Do not use “since” to talk about a quantity of time (two months, five years, a decade, etc.).
- I have loved ballet since I was a little girl. Since I was a little girl, I’ve loved ballet.
- You have been my best friend since first grade.
- Since starting classes, his English has improved significantly. His English has improved significantly since starting classes.
- Since we got married, we’ve moved three times. We’ve moved three times since we got married.
Use “before” when discussing something that occurs earlier than something else.
- Before I go to work, I eat breakfast. I eat breakfast before I go to work.
- We wash our hands before we eat dinner. Before we eat dinner, we wash our hands.
- Before I met you, I was lonely. I was lonely before I met you.
- They like to watch TV at night before they go to bed. Before they go to bed, they like to watch TV.
Use “ago” when talking about something that happened in a certain time in the past.
- I met you eight years ago when we were in college.
- Her daughter was born 3 months ago.
- They finished the race an hour ago.
- Two years ago, I was unhealthy and out of shape. Now I eat well an exercise and am healthier than ever!