'agree' is a verb followed only by the 'to infinitive'.

'admit' is a verb followed only by a gerund.

'forget' can be following by gerund or 'to infinitive'. However, when 'forget' is followed by the gerund it means you forget something you HAVE done e.g. I'll never forget meeting Harry Styles. When 'forget' is followed by the 'to infinitive', it's something you need to do and you forget to do it - so you have NOT done it. She didn't lock the door as the house was then burgled. So it's 'to infinitive'.

It is bare infinitive because verbs of perception (see, hear, feel, etc.) are followed by a bare infinitive when they indicate a complete action. We only use 'ing' if we are indicating the ongoing nature of an event we are perceiving.

The causative 'let' is followed by object + bare infinitive and cannot be followed by verb+ing or to + infinitive

Verbs of perception are followed by object + bare infinitive when it's a completed action. You might use 'playing' if you want to emphasise the ongoing nature of it but 'play' would be more common if it's a finished action.

The causative verb 'make' is followed by object + bare infinitive. It cannot be followed by object + verb-ing.

'plan' is a verb followed only by 'to + infinitive'.

'need' is a verb followed only by 'to + infinitive'.

If 'suggest' is followed by a verb, it's the gerund form. If we put in an object we can use the bare infinitive e.g. 'I suggest (that) you arrive early'.

The verb 'help' is followed by the bare infinitive.

Though the rule is 'make + object + bare infinitive', we can use 'to + infinitive' after 'make' when it's passive and with no object.

'decide' is a verb followed by 'to + infinitive'

Modal verbs are followed by the bare infinitive.

The verb 'important' is followed by 'to + infinitive' though if we put in an object we can use the bare infinitive e.g. 'It's important you arrive early'.

The verb 'enjoy' is followed by a gerund.

Expressions like "had better" and "would rather" take the bare infinitive.

Verbs of perception are followed by object + bare infinitive when it's a completed action.

Though 'help' alone is followed by the bare infinitive, we use a gerund here because the phrase "can't help" is always followed by a gerund to express an involuntary reaction.

The verb 'want' is followed by 'to + infinitive'.