Usage of one time

1.once, when used as a conjunction, means "Once you start, don't give up.

Once you start reading, you will like it. Once you start reading, you will like it.

Physics is easy to learn. Once you understand the law, physics is not difficult to learn. Note: once leads to the adverbial clause of time, and the clause should use the general present tense, not the future tense.

When used as an adverb, it means "once"; Once; Once upon a time "is an indefinite adverb, and its position is generally before the action verb and after the copula verb.

For example, I used to live in America, but I didn't live in England.

He used to live in America, but now he lives in England.

His songs used to be the best among young people. His songs used to be very popular with young people.

myfatheronceemployedayyoungmannamedjohnson。

My father once hired a young man named Johnson.

Once as an adverb also means "once". Two times is "twice", three times is "three times" and four times is "four times". The old professor comes to see us once a week. Tell us the story again.

Note that once, when used as an adverb, has different meanings in different positions in the sentence, so pay special attention to it. For example:

Ioncewenttoshanghai。 I have been to Shanghai. I have been to Shanghai.

5.5. Usage of some phrases formed by once:

(1)atonce (immediately; Immediately)

Allofyoushouldgothereatonce。 All of you should go there at once.

Complete the task at once. Please finish.

(2)onceagain (again; Once again), equivalent to oncemore.

Let me hear you sing again.

Readthepassageoncemore。

(3)onceinawhile (occasionally; Occasionally)

We go to see our English teacher occasionally.

Allatonce (suddenly) is equivalent to suddenly.

Once, they rushed into the toilet. Suddenly, they all rushed out together.

(5)onceuponatime； Previously)

Once upon a time there was an old man named john seale.