Verb form may be classified as follows:
Base form - after modal
· She can sing well. (She sings well à without modal)
· The police artist will draw the criminal’s face.
· I must write the paper now for tomorrow’s discussion.
· He should let the dog out in the evening.
Infinitive - to show purpose
· He set aside his salary to start his own business.
· To write well, we must practice writing a lot.
· He is working part time in order to finish his thesis.
· It was thoughtful of her to buy me a watch.
· The doorbell is too high to ring.
· My father is very fond of reading.
· I’m thingking of writing another novel.
· John is looking forward to running his father’s store.
· The principal wan enraged by the student’s behavior.
· The contract has been signed.
· The students behavior had enraged the principal.
· Mr. Hung has signed the contract.
Simple past form
· I started to cry as I listened to his account.
· He wrote a letter to say that he could’t come to New York.
· Donny saw Andy off to the office.