Conjunctions of Time
In everyday life, we often perform two or more actions sequentially or simultaneously. For example, I eat before I take a shower, or I listen to music while I study.
Words like before and while in those sentences function to sequence the timing of multiple events. In English, these are called Conjunctions of Time, which are a subcategory of Subordinating Conjunctions.
Common Conjunctions of Time
Here are some of the most frequently used time conjunctions to connect two clauses:
| Conjunction | Function |
|---|---|
| When | Indicates a specific point in time when something happens. |
| While | Indicates two things happening at the exact same time over a period. |
| Before | Event A happens prior to Event B. |
| After | Event A happens subsequent to Event B. |
| Until / Till | Indicates the endpoint of an action. |
| Since | Indicates the starting point of an action. |
| As soon as | The second action happens immediately after the first is finished. |
Usage Examples in Sentences
Let’s see how these conjunctions work to connect two clauses (sentences) into one cohesive unit:
1. When vs. While
Both are often confusing, but they have distinct functional differences:
- When is used for events that happen at a single point in time, or interrupt another event.
- The phone rang when I was sleeping.
- While is used for two events that have duration (last for a while) and occur simultaneously.
- I was reading a book while he was watching TV.
2. Before vs. After
- Wash your hands before you eat.
- I will call you after I arrive at the hotel.
Remember the comma rule: If the conjunction is in the middle, no comma is needed. If it’s placed at the front of the sentence: After I arrive at the hotel, I will call you.
3. Until vs. Since
- We will wait here until the rain stops.
- She has lived in New York since she was a child.
4. As soon as
Used to show that there is no time delay between the completion of the first event and the start of the second event.
- I will tell him the news as soon as he arrives.
Since/Until as Prepositions vs. Conjunctions
Often, since, until, before, and after also act as prepositions. The way to differentiate them is the same as in previous materials: look at what comes after the word!
- As a Preposition: Followed ONLY by a noun / time phrase.
- I will wait until tomorrow.
- I haven’t eaten since morning.
- As a Conjunction: Followed by a full CLAUSE (Subject + Verb).
- I will wait until you come back.
- I haven’t eaten since I woke up.