Date Published: Sept. 24, 2016, 11:19 p.m.
Adverb clauses are subordinate/ dependant clauses, which means they cannot stand alone as complete sentences: An adverb clause must join to an independent clause to make a complete sentence. Adverb clauses connect to independent clauses using subordinating conjunctions such as when, if, although, where, because and several others. Basically, subordinating conjunctions refer to time, condition, contrast, place, and cause and effect.
Adverb clauses of time begin with subordinating conjunctions like before, after, since, while, as, when, by the time, every time, whenever, until, till, as soon as, and as long as. The important thing will often be which verb tense to use. In all cases, do not use the word will in an adverb clause of time to refer to the future; instead, use the simple present:
will go to bed, I should brush my teeth.
Before I go to bed, I should/will/always brush my teeth.
When the adverb clause of time begins with since, use the present perfect in the main clause because since tells us the starting time for an event, activity or situation which continues to the present:
Since I started working at this company, I have met many interesting people.
You can switch the order of clauses, but be sure to keep the conjunction with the correct clause:
I have met many interesting people since I started working here.
The words as, while, and when are used to indicate background activity for another event.
As I was preparing to leave, a stranger approached.
While she was drinking her wine and relaxing, a thought occurred to her.
When I’m working on my reports at night, she often calls.
As you can see from the above, the word when does not always go with a non-continuous verb.
Likewise, while does not have to go with continuous verbs, although they are often preferred for longer background activity:
While I was painting the house, Sally stopped by.
There are some verbs that are commonly used in a simple tense with while such as lie, sit, pick, cut, speak and others. A lot of times the verb will be followed by an -ing form:
While I lay there thinking about my success, I heard a knock at the door.
Not Mere Background
Sometimes neither action is considered a background activity giving context to the main point when two actions happen at the same time:
Please wait here while I speak to your teacher.
Notice that while I speak to your teacher seems to actually be the point.
When talking about two things that you usually or regularly do together, or that you did together in the past, you can use while with simple present or past verbs:
I watch TV while I prepare dinner.
I wrote a letter while I thought about the problem.
To just say that two relatively longer events or activities happened at the same time, use simple or continuous verbs with while:
I was doing some research online while my boss was conferencing with some clients.
I walked the dogs while she cleaned the kitchen.
If two simultaneous events seem to progress together, use as with simple tense verbs:
As he listened to the story, he became furious.
You could say As he was listening to the story, but then listening to the story appears as more of a background activity. It is grammatically correct, but doesn’t stress the notion of anger becoming progressively stronger as each part of the story is revealed. The effect is stronger if you substitute while for as.
As he built his empire, he realized that keeping peace was as difficult as making war.
The idea is that over the whole period of time spent on building his empire, he increasingly became aware that keeping peace was as difficult as making war.
As he was building his empire, he realized that keeping peace was as difficult as making war.
Again, this construction, while grammatically correct, reduces building his empire to a background activity and doesn’t capture the very close causal relation between building the empire and realizing something about peace and war. Again, the effect is stronger if you substitute while for as.
First Things First
The words before and after don’t give learners much problem. They both specify that one action is first and another is second. Usually, you can use a simple form or a perfect form. A perfect form stresses completion of an activity where possible. If you do use a perfect form, make sure it’s in the correct clause:
With after, the time clause can have either form:
I will leave the room after I turn off the light
I will leave the room after I have turned off the light.
I left the room after I turned off the light.
I left the room after I had turned off the light.
It’s hard to really stress the idea of completion for turn off the light, so the perfect form is unnecessary, though it is grammatically acceptable.
With before, the main clause can have either form:
I will prepare dinner before she arrives.
I will have prepared dinner before she arrives.
I had prepared dinner before she arrived.
I prepared dinner before she arrived.
Here too, there is little if any difference between the simple and perfect form.
There is an exception when using before in which the past perfect refers to a later action than the action in the main clause:
I turned around and walked away before she had made it through her explanation.
Here, she started talking to me, but before she could finish, I had walked away.
By the Time
The phrase by the time is used to say that one action or event is completed before another. This phrase is very commonly misused by students with interesting results. For example the sentence
By the time I finish my exam, I will go out for a drink.
doesn’t mean I will finish my exam and then go out for a drink. The verb form in the second clause is incorrect, but if anything, the sentence means I will start my exam and then go out for a drink and then come back and finish my exam. That’s an interesting approach, but I don’t think your instructor will go for it.
At its simplest, the phrase by the time takes a simple past or simple present verb in the time clause, and a perfect form in the main clause:
By the time she gets home, I will have prepared dinner.
By the time she got home, I had prepared dinner.
In both cases, prepare dinner is completed before she gets home.
Sometimes a state instead of an action is described in the main clause and a perfect form is not used:
By the time she arrives, he will be drunk.
By the time she arrives, he will have become drunk.
Here, the idea is that he will start drinking before she arrives. He will drink enough to become drunk before she arrives.
By the time he arrived, she was happy.
By the time he arrived, she had become happy.
Notice, she became happy before he arrived. So the reason she is happy is not because he arrived. You have to realize that the action or state in the main clause occurs first. So, maybe she was unhappy, but then she met some friends and had a good conversation and she became happy… and then he arrived.
You can also use by the time to talk about repeated events where one thing always happens before another. In this case we use the present perfect in the main clause:
By the time we finish dinner, the sun has always set.
Also, an action may have started but not been completed at the time of the action referred to in the time clause, and in this case a future continuous or past continuous tense may be used:
By the time she reads this, I will be flying over the Pacific. future
By the time she read this, I was flying over the Pacific. Past
The word when has various uses. Often the verb in the when – clause is simple past:
When it started to rain, I went inside.
The action in the when - clause usually happens first.
I stepped out of the house when suddenly a stranger appeared in front of me.
In this case, first I stepped out of the house and then a stranger appeared in front of me.
We can use the past perfect in the main clause and the meaning is similar to by the time and before, but with before the past perfect would not be necessary:
When I got to my car, it had started raining.
Before I got to my car, it started raining.
We can also use the past perfect in the when - phrase to indicate that the action in that phrase was completed before the action in the second:
When I had read the letter, I began to prepare dinner.
Here, reading the letter is quite independant of preparing dinner. There is no causal relation.
To indicate a causal relation, we often use the simple past with when:
When I read the letter, I began to worry.
We can use when to refer to stages and periods of time in one’s life:
When I was a student/ When I was in school, I enjoyed studying.
We can use when and while to refer to some past event:
When I was in Japan/ While I was in Japan, I visited several temples.
Very generally speaking, when an adverb clause of time comes before the main clause, a comma is used after the time clause. When the main clause is first, a comma is not necessary and is often not used.
When in doubt, return here or check another source. While you are studying, write sentences that are very similar and consider if they imply some difference in meaning and if they are in fact acceptable. By the time you master adverb clauses of time, you will have written hundreds of sentences, I suspect.
Attached File: time activity
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