Infinitives with and  without to

We usually put the marker to before the infinitive.

• I want to go.
• She wants to sing.
• It is nice to meet you.
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In some cases we use the infinitive without to.
. After modal auxiliary verbs
The infinitive is used without to after modal auxiliary verbs will, shall, would, should, can, could, may, might and must.

• It might rain later in the evening. (NOT It might to rain later in the evening.)
• I must go now. (NOT I must to go now.)
• She should have resigned. (NOT She should have to resigned.)

The infinitive without to can also be used after had better, need and dare.

• You had better see what she wants.
• You need not wait.

After let, make, hear etc.
The verbs let, make, see, hear, feel, watch and notice are followed by object + infinitive without to.

• They made me wait. (NOT They made me to wait.)
• I saw him slap the child. (NOT I saw him to slap the child.)
• I don’t let my children stay up late.
• Did you hear him say that he was leaving?

Help can be followed by an infinitive with or without to.

• She helped me to unload my car. OR She helped me unload my car.

In passive forms with make, see, hear, help and know we use infinitives with to.

• I was made to wait. (NOT I was made wait.)
• He was helped to lift the box.