Nine cases of omitting to in infinitive

First, the case of omitting to after the causative verb.

Infinitives used as object complements after causative verbs such as let, make and have must omit to. For example:

My mother will never let me go to the movies. My mother won't let me go to the movies.

I don't like milk, but my mother let me drink it. I don't like milk, but my mother forces me to drink it.

I want him to wait for me at the park gate. I want him to wait for me at the park gate.

note:

1. When causative verbs are used in passive voice, to ellipsis should be added in active voice (mainly make, let and have are rarely used in passive voice).

2. Force, goal, etc. Although they also mean "make", the infinitives used as object complements after them must take to. For example:

He forced me to go with them. He forced me to go with them.

The police forced him to leave. The police forced him to leave.

Second, the situation of omitting to after the sensory verb.

An infinitive used as an object complement after a sensory verb must omit to. For example:

I watched her get on the bus. I watched her get on the bus.

I saw that woman enter a bank. I saw this woman enter a bank.

We often hear her sing this song.

Did you notice that she left the house? Did you notice that she left the house?

note:

1. The sensory verbs mentioned here mainly include watching, listening, observing, paying attention, feeling and watching. But when they are used in passive voice, infinitives must be followed by to. For example:

The woman was seen walking into a bank. The woman was seen walking into a bank.

However, the verbs notice and watch used in the above sentence patterns are usually not used in the passive voice.

2. Similarly, the infinitive used as the object complement after the verb look and listen do take to. For example:

We listened to the old man tell his story. We listened to the old man tell his story.

3. If the infinitive used as the object complement after the verb feel is to be, take to (without to in other cases). For example:

They think this plan is unwise. They think this plan is unwise.

4. If the infinitive is perfect, you should usually use to. For example:

I noticed that she came early. I noticed that she came early.

Third, the case of omitting to after the verb help.

The infinitive used as an object or object complement after the verb help can not be used with to. For example:

Can I help carry this heavy box? Can I help carry this heavy box?

My mother helps me with the housework. Mom helps me with my homework.

note:

1. When help is followed by a long noun phrase as the object, or when the action subject represented by the infinitive is not directly involved, the infinitive usually takes to. For example:

Help the little boys at the back of the hall move their chairs out. Please help those little boys at the back of the hall to move their chairs out.

These pills help you sleep. These pills help you sleep.

When help is used in the passive voice, the to before the infinitive cannot be omitted. For example:

A woman helped the boy collect his scattered coins. A woman helped the boy pick up the scattered coins.

Fourth, why (not) ... after the omission.

Why (not) ... The infinitive that follows cannot be used. For example:

Why go with him? Why go with him?

Why not ask the teacher? Why not ask the teacher?

Why not try to write your story into a novel? Why don't you expand your story into a novel?

Verb (abbreviation of verb) After the verb know, omit to.

In "know+object+infinitive", infinitive sometimes omits to, and sometimes unconscious, which can be discussed in the following two situations:

1. If know is the present tense, the infinitive in this structure is only to be, and to cannot be omitted. For example:

I know he is ill. I know he is ill.

We know that she is honest. We know that she is honest.

2. If know is the perfect or past tense, the infinitive in this structure can use verbs other than to be, in which case, to can be omitted. For example:

I never knew that he would do such a thing. I have never heard that he would do that.

We have never heard of him telling a lie. We have never heard that he lied.

I never knew it would snow in July. I have never heard of snow in July.

But in the passive voice, the to before the infinitive cannot be omitted. The use of "know" in this way not only means "know" in the general sense, but also means an experience, so it is often translated as "once ......................."

Sixth, the situation of omitting to after the preposition except/but.

The infinitive is used as the object of the preposition except, but sometimes with to and sometimes without to. The general principles are as follows: if the verb do appears before it, the infinitive after it usually does not take to; If the verb do does not appear before it, the infinitive after it usually uses to.

For example:

I have no choice but to wait. I have no choice but to wait.

He just wants to stay there. He just wants to stay there.

It has no effect except to make him angry.

She knows everything except cooking. She knows everything except cooking.

Seven, the subject omits to with the do predicative.

When the subject part has some form of verb do, the infinitive used as predicative can omit to. For example:

All you have to do now is fill out the form. What you have to do now is to fill in this form.

The only thing we can do now is to continue. Forward is the way out now.

What I have to do is tell her the truth. All I have to do is tell her the truth.

Eight, omitting to in the coordinate infinitive.

When two or more infinitives with the same function are juxtaposed, it is usually only necessary to use to before the first infinitive, and to can be omitted before other infinitives. For example:

He asked me to stay there and wait for him. He told me to wait for him there.

I really don't know what to think or say. I really don't know what to think and say.

It is easier to persuade others than to force them.

However, if there is a contrast between the two, the to before the infinitive cannot be omitted. For example:

Trying to fail is better than not trying at all. Trying to fail is better than not trying at all.

9. Does the ellipsis infinitive keep to?

In a certain context, in order to avoid repetition, infinitives can sometimes be omitted, but the infinitive symbol to is usually kept. For example:

I'll go if I want to. If I want to go, I will go. (from www.nmet 168.com)

"Don't be late." "I'll try not to." "Don't be late." "I try not to be late."

Don't go unless I tell you to. Don't go until I tell you to.

note:

1. If the omitted infinitive is a to be phrase, you should usually keep to be. For example:

He is not the man he used to be. He is not the man he used to be.

2. Sometimes when the infinitive is omitted, to can also be omitted. For example:

She can go if she wants. She can leave if she wants.